U.S. patent application number 17/731135 was filed with the patent office on 2022-08-18 for functionalized particulate bicarbonate as blowing agent, foamable polymer compositon containing it, and its use in manufacturing a thermoplastic foamed polymer.
This patent application is currently assigned to Solvay SA. The applicant listed for this patent is Solvay SA. Invention is credited to Karine Cavalier, Thibaud Louis Alfred Detoisien, Jorge Alejandro Kabbabe Malave, Jean-Philippe Pascal.
Application Number | 20220259396 17/731135 |
Document ID | / |
Family ID | 1000006300263 |
Filed Date | 2022-08-18 |
United States Patent
Application |
20220259396 |
Kind Code |
A1 |
Cavalier; Karine ; et
al. |
August 18, 2022 |
FUNCTIONALIZED PARTICULATE BICARBONATE AS BLOWING AGENT, FOAMABLE
POLYMER COMPOSITON CONTAINING IT, AND ITS USE IN MANUFACTURING A
THERMOPLASTIC FOAMED POLYMER
Abstract
A chemical blowing agent for foaming a thermoplastic polymer,
for example PVC plastisol or a polymer resin in an extrusion
process, said chemical blowing agent comprising a functionalized
particulate bicarbonate containing at least one additive,
preferably excluding an exothermic blowing agent. The additive may
be selected from the group consisting of polymers; inorganic salts;
oils; fats; resin acids, any derivative thereof, and salts thereof;
amino acids; fatty acids; carboxylic or polycarboxylic acids,
soaps; waxes; in derivatives thereof (such as esters); salts
thereof; or any combinations thereof. The particulate bicarbonate
may be functionalized by spray-drying, coating, extrusion or
co-grinding with at least one additive. The functionalized
particulate bicarbonate may comprise 50 wt % to less than 100 wt %
of the bicarbonate component, and 0.02-50 wt % of the additive. A
foamable polymer composition comprising such chemical blowing
agent. A process for manufacturing a foamed polymer, such as foamed
PVC, comprising shaping and heating the foamable polymer
composition, and a foamed polymer obtained by such process.
Inventors: |
Cavalier; Karine;
(Dombasle-Sur-Meurthe, FR) ; Kabbabe Malave; Jorge
Alejandro; (Bourg-La-Reine, FR) ; Pascal;
Jean-Philippe; (Villers Les Nancy, FR) ; Detoisien;
Thibaud Louis Alfred; (Dombasle-Sur-Meurthe, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Solvay SA |
Brussels |
|
BE |
|
|
Assignee: |
Solvay SA
Brussels
BE
|
Family ID: |
1000006300263 |
Appl. No.: |
17/731135 |
Filed: |
April 27, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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16317376 |
Jan 11, 2019 |
|
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PCT/EP2017/068399 |
Jul 20, 2017 |
|
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17731135 |
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62364843 |
Jul 20, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08J 9/0061 20130101;
C08L 27/06 20130101; C08J 2203/02 20130101; C08J 9/08 20130101;
C08J 2427/06 20130101; C08J 2405/02 20130101; C08J 2433/10
20130101; C08J 9/0028 20130101; C08L 2205/025 20130101; C08J
2471/02 20130101; C08J 2405/00 20130101; C08L 2310/00 20130101;
C08L 2203/14 20130101; C08J 3/226 20130101; C08J 2493/04 20130101;
C08J 9/0023 20130101; C08J 2327/06 20130101; C08J 2403/02 20130101;
C08J 2491/06 20130101; C08J 2429/04 20130101 |
International
Class: |
C08J 9/08 20060101
C08J009/08; C08J 3/22 20060101 C08J003/22; C08J 9/00 20060101
C08J009/00; C08L 27/06 20060101 C08L027/06 |
Claims
1.-31. (canceled)
32. A method, comprising: foaming a thermoplastic polymer precursor
with a chemical blowing agent, wherein said chemical blowing agent
comprising a functionalized particulate bicarbonate containing at
least one additive chosen from the following compounds: one or more
polymers; one or more amino acids, any derivative thereof, and
salts thereof; one or more inorganic salts; one or more oils; one
or more fats; one or more resin acids, any derivative thereof, and
salts thereof; one or more fatty acids, any derivative thereof, and
salts thereof; a carboxylic or polycarboxylic acid, derivative
thereof (such as esters), or salts thereof; one or more soaps; one
or more waxes; or any combinations thereof, wherein the
functionalized particulate bicarbonate comprises sodium
bicarbonate, wherein the functionalized particulate bicarbonate
comprises at least 65% by weight and less than 100% by weight of
sodium bicarbonate and from 0.02% to 35% by weight of said at least
one additive.
33. The method according to claim 32, wherein the blowing agent
does not contain any further blowing agent which is an exothermic
blowing agent.
34. The method according to claim 32, wherein the chemical blowing
agent does not contain a compound which liberates nitrogen gas
during heating.
35. The method according to claim 32, wherein the blowing agent
does not contain a compound which liberates ammonia gas during
heating.
36. The method according to claim 32, wherein the additive in the
functionalized particulate bicarbonate is a) at least one compound
selected from the group consisting of an amino acid, derivative
thereof, or salt thereof, wherein the amino acid is selected from
the group consisting of casein, gelatin, glycine, proline,
hydroxyproline, glutamic acid, alanine, arginine, aspartic acid,
lysine, pectin, serine, leucine, valine, phenylalanine, threonine,
isoleucine, hydroxylysine, methionine, histidine, tyrosine, and
combinations thereof; b) at least one compound selected from the
group consisting of a fatty acid, derivative thereof, or salt
thereof, wherein the fatty acid is at least one compound selected
from the group consisting of lauric acid, stearic acid, glycerol
mono stearate, and combinations thereof; c) at least one polymer
selected from the group consisting of polyoxyalkylenes and
derivatives thereof including polyethylene glycols,
poly(meth)acrylates and derivatives thereof, polyvinylalcohol,
polysaccharides, and combinations thereof, wherein the polymer
selected from the group consisting of polyvinylalcohol and
polyoxyalkylenes and derivatives thereof including polyethylene
glycols; wherein the polysaccharides are selected from the group
consisting of modified, in particular hydrolyzed starch,
maltodextrin, arabic gum and combinations thereof; d) at least one
resin acid, any derivative thereof, and salts thereof; e) at least
one oil, wherein the oil is a vegetable oil or any derivative
thereof; or f) at least one wax selected from the group consisting
of beeswax, carnauba wax and combinations thereof.
37. The method according to claim 36, wherein the amino acid is
leucine.
38. The method according to claim 36, wherein the amino acid is
lauric acid.
39. The method according to claim 36, wherein the polysaccharide is
maltodextrin.
40. The method according to claim 36, wherein the resin acid is
rosin acid.
41. The method according to claim 36, wherein the oil is epoxidized
soy bean oil.
42. The method according to claim 32, wherein particles of the
functionalized particulate bicarbonate have a particle size
distribution of D50 of more than 1 and at most 250 .mu.m
43. The method according to claim 32, wherein particles of the
functionalized particulate bicarbonate have a particle size
distribution of D50 of at most 1 .mu.m.
44. The method according to claim 32, wherein the functionalized
particulate bicarbonate is obtained by at least one of the
following processes: by spray-drying (also known as atomization),
wherein the additive is dissolved in the bicarbonate-containing
solution; by grinding or co-grinding (also known as milling or
co-milling) with the additive(s) in emulsion or powder form; by
spray coating and granulation within a fluidized bed; by spray
agglomeration within a fluidized bed; by spray chilling, wherein
the spray chilling comprises spray cooling or spray freezing; by
roller compaction; and/or by extrusion, including simultaneous
mixing/extrusion.
45. The method according to claim 39, wherein the functionalized
particulate is further subjected to milling to reduce its mean
particle size.
46. The method according to claim 32, wherein the foaming step
further comprises a second compound which liberates CO.sub.2 upon
heating, said second compound being selected from the group
consisting of a carboxylic or polycarboxylic acid, derivative
thereof, or salts thereof, wherein said second compound is
functionalized with at least one additive which is different or
same as the one in the functionalized particulate bicarbonate.
47. The method according to claim 46, wherein said second compound
is at least one of: fumaric acid, tartaric acid, citric acid,
citrates, or esters of citric acid; or combination thereof.
48. The method according to claim 32, wherein the foaming foams a
foamable polymer composition comprises a polymer, optionally a
foaming stabilizer, and the chemical blowing agent, wherein the
polymer is a PVC, a polyurethane, a polyolefin, or a polyamide.
49. The method according to claim 32, wherein the foaming foams a
foamable PVC plastisol composition, comprising a PVC resin,
optionally a foaming stabilizer, and the chemical blowing agent,
which does not contain azodicarbonamide, benzenesulfonylhydrazide,
and/or p-toluenesulfonylhydrazide.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. provisional
application No. 62/364,843, filed on Jul. 20, 2016, its whole
content being incorporated herein by reference for all
purposes.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
TECHNICAL FIELD OF THE INVENTION
[0003] The invention relates to a functionalized particulate
bicarbonate containing an additive. The invention also relates to a
foamable composition containing it, such as a PVC plastisol, and to
its use/method for manufacturing a thermoplastic foamed polymer, in
particular foamed PVC.
BACKGROUND
[0004] Polymer foams are found virtually everywhere in our modern
world and are used in a wide variety of applications such as
disposable packaging of fast-food, the cushioning of furniture and
insulation material.
[0005] Polymer foams are made up of a solid and gas phase mixed
together to form a foam. By combining the two phases fast results
in foaming and forming a polymer matrix with either gas bubbles or
gas tunnels incorporated in it, which is known as either
closed-cell or open-cell structure. Closed-cell foams are generally
more rigid, while open-cell foams are usually flexible.
[0006] The gas that is used in the foam is termed a blowing agent,
and can be either chemical or physical. Chemical blowing agents are
chemicals that take part in a reaction or decompose, giving off a
gas in the process. Physical blowing agents are gases that do not
react chemically in the foaming process and are therefore inert to
the polymer forming the matrix.
[0007] For the processing of thermoplastic materials, such as
polyvinyl chloride (PVC) or polyolefins (PO, PE, PP), styrenics
(PS, ABS, ASA, SAN) and natural and synthetic rubber such as
nitrile butadiene rubber (NBR) or chloroprene rubber (CR), chemical
blowing agents are used for decades. Chemical blowing agents are
additives in the manufacturing of foamed thermoplastic polymers.
Chemical blowing agents are stable at room temperature but
decompose at elevated temperatures during the processing of the
polymers while generating gas. This gas creates a foam structure in
the thermoplastic polymer. Chemical blowing agents are used in a
wide variety of applications including the production of foamed
wall papers, artificial leather, floor and wall coverings, carpet
backings, thermal insulation materials, insulation sealants,
footwear, automotive components, cable insulation, and packaging
materials.
[0008] Established blowing agents are exothermic blowing agents
such as azodicarbonic acid diamide (azodicarbonamide, ADC, ADCA,
CAS No. 123-77-3), the sulfonhydrazides
4,4'-oxybis(benzenesulfonylhydrazide) (OBSH, CAS No. 80-51-3) and
p-toluenesulfonylhydrazide, (TSH, CAS No. 1576-35-8) and
endothermic blowing agents such as carbonates, like sodium
bicarbonate (SBC, NaHCO.sub.3, CAS No. 144-55-8), and citric acid
and its esters.
[0009] Since many years, azodicarbonamide (ADC) is one of the most
effective and widely used chemical blowing agents for use in
cellular thermoplastic and rubber applications (cf for example
DE-AS 1 037 700). Azodicarbonamide decomposes on heating to give a
high volume of gas, which consists mainly of nitrogen and carbon
monoxide. These decomposition products are suitable to create a
fine and uniform cell structured foam with a little shrink, a
property which is fundamental in the production of soft foams such
as plasticized PVC (P-PVC) or rubber foams. The decomposition
temperature of azodicarbonamide can be reduced from 200-220 degrees
centigrade to as low as 125 degrees centigrade by the addition of
suitable activators (kickers), but useful decomposition rates are
usually only achieved at 140 degrees centigrade and above.
Activators or kickers are additives known in the art which are used
to influence the decomposition temperature and rate of gas release
of the blowing agent.
[0010] Azodicarbonamide may be combined with other chemical blowing
agents in order to improve the processing behavior of the
thermoplastic material and to optimize the end product. For
example, in cellular rigid PVC (U-PVC; without softening of the
polymer by adding plasticizers) applications such as foamed profile
or sheet, ADC may be used in combination with sodium bicarbonate to
produce a foam structure with acceptable technical performance
(GB2314841). Because of differences in melt rheology, processing
and demands on the foam structure, this technique cannot be
transferred to plasticized, soft PVC and PVC plastisol
processing.
[0011] However, azodicarbonamide as a blowing agent in plastics has
been banned in the European Union since August 2005 for the
manufacture of plastic articles that are intended to come into
direct contact with food (COMMISSION DIRECTIVE 2004/1/EC of 6 Jan.
2004 amending Directive 2002/72/EC as regards the suspension of the
use of azodicarbonamide as blowing agent". Official Journal of the
European Union. 2004 Jan. 13).
[0012] Furthermore, in December 2012, the European Chemicals Agency
(ECHA) announced that azodicarbonamide was to be included in their
Candidates List of Substances of Very High Concern (SVHC) under
Articles 57 and 59 of the Reach Regulation, which will limit or
restrict the future use of ADC. Therefore, there is a need for
substitutes for ADC having the same beneficial performance,
especially for applications in foamed PVC.
[0013] Possible alternative solutions are provided by the classes
of sulfonylhydrazides and carbonates, but these substances exhibit
some disadvantages when used as blowing agents, especially when
used for applications in plasticized, soft PVC.
[0014] p-Toluenesulfonylhydrazide (TSH) starts decomposition at a
temperature of about 105 degrees centigrade, which is considered as
being too low for the processing of rigid and plasticised PVC.
4,4'-Oxybis(benzenesulfonylhydrazide) (OBSH) also releases nitrogen
upon decomposition but the gas generation characteristic is
different to that of azodicarbonamide. At temperatures above the
decomposition point of OBSH the nitrogen release is rapid, but
occurs at a different temperature compared to azodicarbonamide.
Below the absolute product decomposition temperature of about 155
degrees centigrade, the decomposition and thus the gas release is
slow. Additionally OBSH has the disadvantage that the decomposition
products and the foamed end article produced have an unintended
brownish discoloration at the typical P-PVC processing temperatures
which are higher than 180 degrees centigrade
[0015] The carbonates such as sodium bicarbonate do not liberate
nitrogen but carbon dioxide and possibly water upon decomposition.
Typically for carbon dioxide is its high solubility in the polymer,
but it permeates out of the polymer matrix more rapidly than
nitrogen, making it less efficient as a foaming agent, especially
in plasticized PVC applications. The carbonates are generally not
useful for the production of soft foams with a fine and uniform
cell structure with little shrink. Sodium bicarbonate, the most
common representative of the carbonates used as chemical blowing
agents, has a slow decomposition and release of gas, which occurs
over a wider temperature range in comparison to both ADC and OBSH.
The decomposition temperature of sodium bicarbonate can be
influenced by citric acid.
[0016] Alkali metal bicarbonate particles, such as sodium
bicarbonate particles and potassium bicarbonate particles, are
known in the art. These products have many properties which make
them interesting and extensively used in several technical fields,
such as pharmaceutical industry, the feed and food industry, in
detergents and in the treatment of non-ferrous metals.
[0017] The most common way to manufacture bicarbonate particles is
crystallization by carbonization with carbon dioxide of a solution
of the corresponding alkali metal (sodium or potassium carbonate
for example) or a solution of the hydroxide of the corresponding
alkali metal. It is also common to crystallize bicarbonates by
controlled cooling of bicarbonate solutions, or by evaporating the
solvent of such solutions.
[0018] For the industrial use of alkali metal bicarbonate particles
control of specific properties of the particles, e.g., their bulk
density (poured bulk density) or angle of repose is required. Some
methods to control these parameters, such as a bulk density are
known in the art. For example, U.S. Pat. No. 5,411,750 discloses a
method of producing sodium bicarbonate powder with a bulk density
between 70 and 500 kg/m.sup.3. The particles are prepared by
spray-drying a dilute aqueous solution of the bicarbonate with an
alkali metal salt as additive. WO 2014/096457 discloses a method
for producing sodium bicarbonate particles by spray-drying of an
aqueous solution comprising 1-10% by weight of sodium bicarbonate
and an additive selected from the group consisting of magnesium
salt, sodium alkyl benzene sulfonate and soybean lecithin.
[0019] The above mentioned non-azodicarbonamide blowing agents fail
to meet the expected requirement profile of a good blowing agent,
and are in need of improvement in this respect.
SUMMARY
[0020] An aspect of the present invention provides a functionalized
particulate bicarbonate, which can be used advantageously as a
non-azodicarbonamide blowing agent in polymer manufacture,
particularly for the preparation of a foamed thermoplastic
material, such as foamed PVC, polyurethanes, polyamides,
polyolefins.
[0021] One aspect of the present invention relates to a
functionalized particulate bicarbonate and its use as chemical
blowing agent for foaming [0022] a thermoplastic polymer, or [0023]
a polymer resin in an extrusion process.
[0024] The additive in the functionalized particulate bicarbonate
may comprise or consist of, as non-limiting examples, at least one
following compound: [0025] one or more polymers; [0026] one or more
amino acids, any derivative thereof, and salts thereof; [0027] one
or more inorganic salts; [0028] one or more oils; [0029] one or
more fats; [0030] one or more resin acids, any derivative thereof,
and salts thereof; [0031] one or more fatty acids, any derivative
thereof, and salts thereof; [0032] a carboxylic or polycarboxylic
acid, derivative thereof (such as esters), or salts thereof [0033]
one or more soaps; [0034] one or more waxes; or [0035] any
combinations thereof.
[0036] The functionalized particulate bicarbonate may be
spray-dried bicarbonate particles in the presence of said additive,
or co-milled bicarbonate particles in the presence of said
additive, or coated with the additive in a fluid bed, or granulated
with the additive in a fluid bed, or coated with the additive in an
extruding device.
[0037] The additive in the functionalized particulate bicarbonate
is more preferably leucine when the functionalized particulate
bicarbonate is spray-dried.
[0038] The functionalized particulate bicarbonate may comprises at
least 50% by weight and less than 100% by weight of the bicarbonate
component, and from 50% to 0.02% by weight of at least one of said
additive. The functionalized particulate bicarbonate may comprise
at least 65% by weight and less than 100% by weight of the
bicarbonate component, and from 35% to 0.02% by weight of at least
one of said additive. The functionalized particulate bicarbonate
may comprise at least 75% by weight and less than 100% by weight of
the bicarbonate component, and from 25% to 0.02% by weight of at
least one of said additive. The functionalized particulate
bicarbonate may comprise at least 90% by weight and less than 100%
by weight of the bicarbonate component, and from 10% to 0.02% by
weight of at least one of said additive.
[0039] Another aspect of the present invention relates to a
chemical blowing agent for foaming a thermoplastic polymer, for
example PVC plastisol or a polymer resin in an extrusion process,
said chemical blowing agent comprising the functionalized
particulate bicarbonate, wherein said functionalized particulate
bicarbonate contains at least one additive.
[0040] In a preferred embodiment, the chemical blowing agent is
endothermic.
[0041] In a preferred embodiment, the chemical blowing agent does
not contain a blowing agent which is exothermic.
[0042] In a preferred embodiment, the chemical blowing agent does
not contain a blowing agent which would liberate nitrogen gas
and/or ammonia during heating when a foamed polymer is made using
such chemical blowing agent.
[0043] In most preferred embodiments, the chemical blowing agent
comprises or consists of the functionalized particulate sodium
bicarbonate.
[0044] In some embodiments, the chemical blowing agent further
comprises a second compound which liberates CO2 upon heating, said
second compound being selected from the group consisting of a
carboxylic or polycarboxylic acid, derivative thereof (such as
esters), or salts thereof. The second compound may comprise or may
be at least one of: [0045] fumaric acid, [0046] tartaric acid,
[0047] citric acid, citrates (such as sodium hydrogen citrate,
disodium citrate), or esters of citric acid; or [0048] combination
thereof. The second compound may be functionalized with at least
one additive which is different or the same as the one used in the
functionalized particulate bicarbonate.
[0049] Another aspect of the present invention relates to a
foamable polymer composition comprising the functionalized
particulate bicarbonate as blowing agent, wherein said
functionalized particulate bicarbonate contains the at least one
additive.
[0050] In some embodiments, the foamable polymer composition
comprises the functionalized particulate bicarbonate as a first
endothermic blowing agent and a carboxylic or polycarboxylic acid,
ester thereof, or salt thereof, as a second endothermic blowing
agent. The carboxylic or polycarboxylic acid, ester thereof, or
salt thereof may be also functionalized. The functionalized
particulate bicarbonate and the functionalized carboxylic or
polycarboxylic acid, ester thereof, or salt thereof may be
functionalized together or separately.
[0051] In particular embodiments, the foamable polymer composition
does not contain a blowing agent which would liberate nitrogen gas
and/or ammonia during heating when a foamed polymer is made from
such foamable composition.
[0052] In some embodiments, the foamable polymer composition does
not contain an exothermic blowing agent.
[0053] During foaming of polymer resin (plastisol or extrusion
process) when particles of non-functionalized sodium bicarbonate
are used as foaming agent, it was observed that the gas release
occurs earlier than expected, due to the quick decomposition of
bicarbonate. It has been found that functionalizing the bicarbonate
particles by coating, by granulation, and/or by encapsulating with
specific additives enhances the protection of the bicarbonate
particles with an inactive barrier, which delays the thermal
decomposition when having various bicarbonate particle sizes, small
(some may be nano-sized) and large (some may be micron-sized).
[0054] The functionalized particulate bicarbonate according to this
aspect of the present invention is preferably a particulate sodium
bicarbonate which is functionalized with at least one additive.
This functionalized particulate sodium bicarbonate shows improved
properties of expansion in comparison with nonfunctionalized
particulate sodium bicarbonate of equivalent size. A
"nonfunctionalized particulate sodium bicarbonate" is defined as a
particulate sodium bicarbonate made without the additive(s) used in
the making of the functionalized particulate sodium bicarbonate.
The functionalized particulate sodium bicarbonate in the foamable
polymer composition may reduce the time of gelation at a
temperature above glass transition temperature Tg and/or above
melting temperature Tm of the polymer. For example for PVC
plastisol, the gelation time at temperature above glass transition
temperature Tg and/or above melting temperature Tm of the polymer
may be less than 90 seconds, preferably 80 seconds or less, or 70
seconds or less, or more preferably 60 seconds or less.
[0055] A process for manufacturing a polymer may comprise heating
the foamable polymer composition which comprises the functionalized
particulate bicarbonate at a temperature suitable for liberating
CO2 gas and melting the polymer during a gelation time at a
temperature above glass transition temperature Tg and/or above
melting temperature Tm of the polymer which is less than 130
seconds.
[0056] For some embodiments of a process for manufacturing a PVC
polymer, when the foamable polymer composition is heated, the
temperature suitable for liberating CO2 gas from the functionalized
particulate sodium bicarbonate and melting a PVC polymer may be
from 190 to 210.degree. C., preferably from 200 to 210.degree. C.,
during a gelation time from 90 seconds to 120 seconds to provide a
foamed PVC polymer.
[0057] When the foamable polymer composition is spread coated on a
surface before heating and polymer melting, the foamed polymer may
have an expansion ratio of at least 270, preferably at least 280,
more preferably at least 300 and/or has a density of less than 0.6
g/cm.sup.3, preferably less than 0.55 g/cm.sup.3, more preferably
at most 0.5 g/cm.sup.3. The expansion ratio is calculated based on
the ratio of a final thickness over an initial thickness of a
spread coated layer of the foamable polymer composition as that
layer gets heated during gelation in an oven.
[0058] The functionalized sodium bicarbonate particles are produced
in the presence of at least one additive from a solution containing
sodium bicarbonate or directly from solid sodium bicarbonate
particles. The additive in the functionalized particulate
bicarbonate may comprise or consist of, as non-limiting examples,
at least one following compound: [0059] one or more polymers;
[0060] one or more amino acids, any derivative thereof, and salts
thereof; [0061] one or more inorganic salts; [0062] one or more
oils; [0063] one or more fats; [0064] one or more resin acids, any
derivative thereof, and salts thereof; [0065] one or more fatty
acids, any derivative thereof, and salts thereof; [0066] a
carboxylic or polycarboxylic acid, derivative thereof (such as
esters), or salts thereof [0067] one or more soaps; [0068] one or
more waxes; or [0069] any combinations of two or more thereof.
[0070] In some embodiments, the additive may comprise or consist of
a polymer selected from the group consisting of polyvinylalcohol,
polyglycol, polysaccharide, poly(meth)acrylic acid, poly(acrylic
acid co-maleic acid, polyethylenenimine, polyvinylpyrrolidone,
N-2(-Hydroxypropyl) methacrylamide, polyoxyalkylenes and
derivatives thereof including polyethylene glycols, and
combinations thereof.
[0071] In some embodiments, the additive may comprise or consist of
a polysaccharide selected from the group consisting of hydrolyzed
starch, carboxymethylcellulose, alginic acid and its salt, arabic
gum, carrageenan; guar gum, locust bean gum, xantham gum and
combinations thereof.
[0072] In some embodiments, the additive may comprise or consist of
an amino acid, derivative thereof, or salt thereof selected from
the group consisting of casein, gelatin, glycine, proline,
hydroxyproline, glutamic acid, alanine, arginine, aspartic acid,
lysine, pectin, serine, leucine, valine, phenylalanine, threonine,
isoleucine, hydroxylysine, methionine, histidine, tyrosine and
combinations thereof.
[0073] In some embodiments, the additive may comprise or consist of
an inorganic salt selected from the group consisting of silicates
(e.g., sodium silicate), NaCl, KCl, MgCl2, sodium phosphate,
borates, nitrates, nitrites, sulfates, sulfites and combinations
thereof.
[0074] In some preferred embodiments, the additive may comprise or
consist of: [0075] an amino acid, derivative thereof, or salt
thereof, [0076] a polysaccharide (such as hydrolyzed starch,
carboxymethylcellulose), [0077] a carboxylic or polycarboxylic
acid, derivative thereof (such as esters), or salts thereof [0078]
a resin acid, derivative thereof, or salt thereof, [0079] a
fatty-acid, derivative thereof, or salt thereof, or [0080] any
combination thereof.
[0081] In some preferred embodiments, the additive may comprise or
consist of: [0082] a polymer (such as polyoxyalkylenes and
derivatives thereof including polyethylene glycols,
poly(meth)acrylates and derivatives thereof, polyvinylalcohol and
polysaccharides, including modified, in particular hydrolyzed
starch, maltodextrin and arabic gum), [0083] an amino acid,
derivative thereof or salt thereof (such as leucine), [0084] an oil
(such as epoxidized soy bean oil), [0085] a resin acid, derivatives
thereof, or salt thereof (such as rosin acid), [0086] a fatty acid,
derivatives thereof, or salt thereof (such as stearic acid, lauric
acid, linoleic acid and glycerol mono stearate), [0087] a wax (such
as bees wax and carnauba wax), or, [0088] any combination of two or
more thereof.
[0089] In some preferred embodiments, the additive may comprise or
consist of: [0090] an amino acid, derivative thereof, or salt
thereof, [0091] a polysaccharide (such as hydrolyzed starch,
carboxymethylcellulose), [0092] a carboxylic or polycarboxylic
acid, derivative thereof (such as esters), or salts thereof [0093]
a resin acid, derivative thereof, or salt thereof, [0094] a
fatty-acid, derivative thereof, or salt thereof, or [0095] any
combination thereof.
[0096] In more preferred embodiments, the additive may comprise or
consist of: [0097] a polyoxyalkylene or a derivative thereof
including a polyethylene glycol, [0098] a poly(meth)acrylate or a
derivative thereof, [0099] polyvinylalcohol [0100] starch,
maltodextrin or arabic gum, [0101] leucine, [0102] an epoxidized
soy bean oil, [0103] rosin acid or a derivative thereof, [0104]
stearic acid, lauric acid, linoleic acid, or glycerol mono
stearate, [0105] beeswax or carnauba wax, or, [0106] any
combination of two or more thereof.
[0107] It should be understood that one or more elements from these
lists may be omitted.
[0108] The functionalized particulate bicarbonate can be obtained
by at least one of the following processes: [0109] by spray-drying
(also known as atomization), wherein the additive is dissolved in
the bicarbonate-containing solution. [0110] by grinding or
co-grinding (also known as milling or co-milling) with the
additive(s) in emulsion or powder form; [0111] by spray coating and
granulation within a fluidized bed, [0112] by spray agglomeration
within a fluidized bed, [0113] by spray chilling (e.g., spray
cooling, spray freezing), [0114] by roller compaction, and/or
[0115] by extrusion, including simultaneous mixing/extrusion.
[0116] It should be understood that one or more methods from this
list may be omitted.
[0117] In preferred embodiments, the functionalized particulate
bicarbonate can be obtained by at least one of the following
processes: [0118] by grinding or co-grinding (also known as milling
or co-milling) with the additive(s) in emulsion or powder form;
[0119] by spray coating and granulation within a fluidized bed,
and/or [0120] by extrusion, including simultaneous
mixing/extrusion.
[0121] The functionalized particulate bicarbonate which is obtained
by at least one said process may be further subjected to milling to
reduce its mean particle size.
[0122] The functionalized particulate bicarbonate shows excellent
CO.sub.2 release properties. As determined by TGA analysis, the
maximum loss temperature of the functionalized particulate
bicarbonate is preferably higher than the non-functionalized
bicarbonate without additive. The CO.sub.2 release of the
functionalized particulate bicarbonate typically has its maximum at
a temperature of at least 130.degree. C., preferably at a
temperature of at least 135.degree. C., more preferably at a
temperature of at least 140.degree. C., even more preferably at a
temperature of at least 145.degree. C., and particularly preferably
at a temperature of at least 155.degree. C.
[0123] As determined by DSC thermal analysis, the maximum peak
temperature of the functionalized particulate bicarbonate is
preferably higher than the non-functionalized bicarbonate without
additive. The DSC maximum peak temperature of the functionalized
particulate bicarbonate may be at least 140.degree. C., preferably
at least 145.degree. C., more preferably at least 150.degree. C.,
even more preferably at a temperature of at least 155.degree. C.,
and particularly preferably at least 160.degree. C.
DETAILED DESCRIPTION
Definitions
[0124] In the present description, wherein an element or
composition is said to be included in and/or selected from a list
of recited elements or components, it should be understood that in
related embodiments explicitly contemplated here, the element or
component can also be any one of the individual recited elements or
components, or can also be selected from a group consisting of any
two or more of the explicitly listed elements or components.
[0125] Further, it should be understood that elements and/or
features of an apparatus, a process or method described herein can
be combined in a variety of ways without departing from the scope
and disclosures of the present teachings, whether explicit or
implicit herein.
[0126] The term "thermoplastic material" shall mean a polymer that
becomes pliable or moldable above a specific temperature, so is
capable of flow at high temperatures below the thermal
decomposition temperature and returns to a solid state upon
cooling. A polymer is a macromolecular compound prepared by
reacting (i.e. polymerizing, condensation) monomers of the same or
different type, including homo- and copolymers. Thermoplastic
materials are made by chain polymerization, polyaddition and/or
polycondensation.
[0127] The term "functionalized particulate bicarbonate" is to be
understood as defining particles which comprise a bicarbonate and
an additive, preferably within the same particle. For example, the
additive may form a layer or coating on the bicarbonate or the
bicarbonate may form a layer or coating on the additive.
Alternatively or additionally the additive may be embedded within a
matrix of the bicarbonate or vice versa. The particle comprising
bicarbonate and additive may be an agglomeration of smaller
particles or small particles of one of the components may be
agglomerated to a larger particle (or larger particles) of the
other component. Preferably, the term "functionalized particulate
bicarbonate" does not include a mere mixture of bicarbonate
particles and at least one additive whether it be in liquid form or
in the form of particles.
[0128] The term "functionalizing additive", as used herein, refers
to a compound that is capable of improving at least one CO.sub.2
release property of sodium bicarbonate when the additive is
formulated with the sodium bicarbonate, relative to the sodium
bicarbonate alone (without additive). For example, the
functionalizing additive is capable of increasing the CO.sub.2
release beginning temperature and/or the CO.sub.2 release maximum
temperature of the functionalized particulate bicarbonate,
determined in accordance with Example 54 of the present
application.
[0129] The term "comprising" includes "consisting essentially of"
and "consisting of".
[0130] The term "foamed" in connection with the terms
"thermoplastic material", "polymer" and "PVC" shall mean such
material, polymer, or PVC with a cellular structure which is formed
by gas generation from thermal decomposition and/or chemical
reaction of a chemical blowing agent during processing.
[0131] The term "ppm" means parts per million, expressed by weight
(e.g., 1 ppm=1 mg/kg).
[0132] The term "pcr" means parts by weight of resin (e.g., 80 per
of additive=80 g additive per 100 g of resin).
[0133] The sign "%" or "wt %" refers to "weight percent" unless
specifically stated otherwise.
[0134] The term "powder" shall mean a compound consisting of milled
(ground), extruded, or spray-dried solid particles.
[0135] The term "exothermic blowing agent" defines a chemical that
generates heat during its decomposition. An exothermic blowing
agent typically undergoes rapid decomposition in a narrow
temperature range. Generally speaking, the exothermic chemical
blowing agents are associated as those chemicals giving N.sub.2 as
the main blowing gas (>50 vol % of the generated gas is
N.sub.2). Other minor gases though may evolve from the
decomposition of the exothermic chemical blowing agent. These other
minor gases may include carbon monoxide, also in small amounts
(<5 vol %) of ammonia, and/or CO.sub.2.
[0136] The term "endothermic blowing agent" defines a chemical that
absorbs heat during its decomposition. An endothermic blowing agent
typically has broader decomposition ranges in terms of both
temperature and time. Most endothermic chemical blowing agents
generate CO.sub.2 as the main blowing gas (>50 vol % of the
generated gas is CO.sub.2).
[0137] The CO.sub.2 release properties of the functionalized
particulate bicarbonate according to one aspect of the present
invention can be determined by performing a thermogravimetric
analysis (TGA) of a functionalized particulate bicarbonate sample,
measuring the weight loss of the sample in dependence of the
temperature. The CO.sub.2 release properties are characterized by
the derivate value for weight loss depending on the temperature.
The CO.sub.2 release beginning temperature is the temperature where
the derivate value for weight loss starts to raise. The CO.sub.2
release maximum temperature is the temperature where the derivate
value for weight loss is at maximum. Typically, heating is
performed between 30.degree. C. and 250.degree. C. at a speed of
10.degree. C./min. Thermogravimetric analysis can be performed for
example on an STD Q600 V20.9 Build 20 thermogravimetric analysis
instrument (provided by TA Instruments).
[0138] A plurality of elements includes two or more elements.
[0139] The phrase `A and/or B` refers to the following selections:
element A; or element B; or combination of elements A and B (A+B).
The phrase `A and/or B` is equivalent to at least one of A and B.
The phrase `A and/or B` equates to at least one of A and B.
[0140] The phrase `A1, A2, . . . and/or An` with n.gtoreq.3
includes the following choices: any single element Ai (i=1, 2, . .
. n); or any sub-combinations of from two to (n-1) elements chosen
from A1, A2, . . . , An; or combination of all elements Ai (i=1, 2,
. . . n). For example, the phrase `A1, A2, and/or A3` refers to the
following choices: A1; A2; A3; A1+A2; A1+A3; A2+A3; or
A1+A2+A3.
[0141] In the present specification, the description of a range of
values for a variable, defined by a bottom limit, or a top limit,
or by a bottom limit and a top limit, also comprises the
embodiments in which the variable is chosen, respectively, within
the value range: excluding the bottom limit, or excluding the top
limit, or excluding the bottom limit and the top limit.
[0142] In the present specification, the description of several
successive ranges of values for the same variable also comprises
the description of embodiments where the variable is chosen in any
other intermediate range included in the successive ranges. Thus,
for illustration purpose, when it is stated that "the element X is
generally at least 10, advantageously at least 15", the present
description also includes another embodiment where a new minimum
can be selected between 10 and 15, for example: where "the element
X is at least 11", or also where: "the element X is at least
13.74", etc.; 11 or 13.74 being values included between 10 and 15.
Also for illustration purpose, when it is indicated that "the
element X is generally at most 15, advantageously at most 10", the
present description also includes another embodiment where a new
maximum can be selected between 10 and 15.
[0143] In the present description, wherein an element or
composition is said to be included in and/or selected from a list
of recited elements or components, it should be understood that in
related embodiments explicitly contemplated here, the element or
component can also be any one of the individual recited elements or
components, or can also be selected from a group consisting of any
two or more of the explicitly listed elements or components. For
example, when in an embodiment the choice of an element from a
group of elements is described, the following embodiments are also
explicitly described: [0144] the choice of two or more elements
from the group, [0145] the choice of an element from a subgroup of
elements consisting of the group of elements from which one or more
elements have been removed.
[0146] The use of the singular `a` or `one` herein includes the
plural unless specifically stated otherwise.
[0147] In addition, if the term "about" or "ca." is used before a
quantitative value, the present teachings also include the specific
quantitative value itself, unless specifically stated otherwise. As
used herein, the term "about" or "ca." refers to a +-10% variation
from the nominal value unless specifically stated otherwise.
Functionalized Particulate Bicarbonate
[0148] One aspect of the present invention relates to a
functionalized particulate bicarbonate.
[0149] The functionalized particulate bicarbonate comprises a
bicarbonate ingredient which preferably is an alkali or ammonium
salt, such as sodium bicarbonate, potassium bicarbonate, and
ammonium bicarbonate. Sodium and potassium bicarbonate, in
particular sodium bicarbonate being preferred.
[0150] In some embodiments, the functionalized particulate
bicarbonate preferably comprises at least 50% by weight, or at
least 55% by weight, or at least 60% by weight, or even at least
65% by weight, but less than 100% by weight of the bicarbonate
ingredient (e.g., ammonium, sodium or potassium bicarbonate).
[0151] In some embodiments, the functionalized particulate
bicarbonate may comprise at least 90% by weight, or at least 93% by
weight, or at least 94% by weight, or even at least 95% by weight,
but less than 100% by weight of the bicarbonate ingredient (e.g.,
ammonium, sodium or potassium bicarbonate).
[0152] In some particular embodiments, the functionalized
particulate bicarbonate preferably comprises at least 90% by weight
but less than 100% by weight of an alkali metal bicarbonate. The
functionalized particulate bicarbonate preferably comprises at
least 92% by weight of an alkali metal bicarbonate, at least 93% by
weight, more preferably at least 94% by weight, in particular at
least 95% by weight of the alkali metal bicarbonate, in particular
sodium bicarbonate.
[0153] In some embodiments, the functionalized particulate
bicarbonate may have 50% by weight or less, or 45% by weight or
less, or 40% by weight or less, or even 35% by weight or less, of
at least one additive.
[0154] In some particular embodiments, the functionalized
particulate bicarbonate contains 10% by weight or less, or 7% by
weight or less, or 5% by weight or less, or 3% by weight or less,
of the additive.
[0155] The additive should be present in the functionalized
particulate bicarbonate according to the present invention in the
amount of at least 0.02% by weight, preferably at least 0.05% by
weight, in particular at least 0.1% by weight. The higher the
weight % of the additive in the functionalized particulate
bicarbonate, the more disadvantageous it will be for cost reasons.
Preferably, to reduce cost of the more expensive additive compared
to the bicarbonate ingredient, it is desirable to use at most 8% by
weight, more preferably at most 6% by weight, in particular at most
5% by weight of the additive in the functionalized particulate
bicarbonate.
[0156] However in embodiments where the additive is relatively not
expensive (for example when its cost is not more than twice that of
the bicarbonate ingredient), it may be desirable to use at least 5%
by weight, more preferably at least 7% by weight, in particular at
least 10% by weight of the additive and/or at most 50% by weight,
more preferably at most 40% by weight, yet more preferably at most
35% by weight in the functionalized particulate bicarbonate.
[0157] In some particular embodiments, the functionalized
particulate bicarbonate may comprise 0.02-50%, or 0.02-45%, or
0.02-40%, or 0.02-35%, by weight of at least one additive.
[0158] In some particular embodiments, the functionalized
particulate bicarbonate may comprise more than 10% and up to 50% by
weight of at least one additive.
[0159] In some embodiments, for cost effectiveness, the
functionalized particulate bicarbonate may comprise from 0.02% to
10% by weight of the additive.
[0160] In particular embodiments, the functionalized particulate
bicarbonate may comprise at least 65% by weight and less than 100%
by weight of the bicarbonate component, and from 35% to 0.02% by
weight of at least one additive; or may comprise at least 75% by
weight and less than 100% by weight of the bicarbonate component,
and from 25% to 0.02% by weight of at least one additive.
[0161] The functionalized particulate bicarbonate is preferably
used as a blowing agent for foamed or extruded polymers (such as
foamed PVC or polyurethanes; extruded PVC, polyolefins,
polyamides), preferably used as an endothermic blowing agent.
Non-limiting examples of polymers are polyvinyl chloride (PVC),
polyurethanes, polyolefins (PO, PE, PP), styrenics (PS, ABS, ASA,
SAN) and natural and synthetic rubber such as nitrile butadiene
rubber (NBR) or chloroprene rubber (CR), polyamides,
polyimides.
[0162] The functionalized particulate bicarbonate may further
contain an additive which is capable of liberating CO2 and which is
also used for functionalizing the particulate bicarbonate. This
additive may be considered as a secondary blowing agent in the
functionalized particulate bicarbonate. Not only this additive
would provide an increase in the CO2 generation when the
functionalized particulate bicarbonate is used as an endothermic
blowing agent, but also this additive would protect the bicarbonate
core from premature CO2 release by protecting its surface (or part
thereof). This CO2-liberating additive may be a carboxylic or
polycarboxylic acid, derivative thereof (such as esters), or salts
thereof.
[0163] Suitable carboxylic acids include those of the formula:
HOOC--R--COOH where R is an alkylene group of 1 to about 8 carbon
atoms which may also be substituted by one or more hydroxy groups
or keto groups and may also contain unsaturation. Also included are
esters, salts and half salts.
[0164] A preferred CO2-liberating additive may include at least one
of: [0165] fumaric acid, [0166] tartaric acid, or [0167] citric
acid, citrates (such as sodium hydrogen citrate, disodium citrate),
or esters of citric acid.
[0168] Esters of citric acid may include tributyl citrate, triethyl
citrate, tri-C12-13 alkyl citrate, tri-C14-15 alkyl citrate,
tricaprylyl citrate, triethylhexyl citrate, triisocetyl citrate,
trioctyldodecyl citrate and triisostearyl citrate, isodecyl citrate
and stearyl citrate, dilauryl citrate, and/or ethyl citrates
(mixture of tri-, di- and monoesters), preferably tributyl citrate,
triethyl citrate, isodecyl citrate, or triethylhexyl citrate.
[0169] A more preferred CO2-liberating additive comprises or
consists of citric acid, esters thereof, or salts thereof.
[0170] In some embodiments, the functionalized particulate
bicarbonate does not contain citric acid, esters thereof, or salts
thereof.
[0171] In some embodiments, the functionalized particulate
bicarbonate does not contain an exothermic blowing agent.
[0172] In some particular embodiments, the functionalized
particulate bicarbonate does not contain a compound used as blowing
agent which liberates ammonia.
[0173] In some particular embodiments, the functionalized
particulate bicarbonate does not contain a compound used as blowing
agent which liberates nitrogen gas. Examples of blowing agents
which liberate nitrogen gas are exothermic blowing agents such as
azodicarbonic acid diamide (azodicarbonamide, ADC, ADCA, CAS No.
123-77-3), the sulfonhydrazides
4,4'-oxybis(benzenesulfonylhydrazide) (OBSH, CAS No. 80-51-3) and
p-toluenesulfonylhydrazide, (TSH, CAS No. 1576-35-8).
[0174] In preferred embodiments, the functionalized particulate
bicarbonate does not contain azodicarbonamide.
[0175] In alternate or additional preferred embodiments, the
functionalized particulate bicarbonate does not contain
benzenesulfonylhydrazide.
[0176] In alternate or additional embodiments, the functionalized
particulate bicarbonate does not contain
p-toluenesulfonylhydrazide.
[0177] In preferred embodiments of the present invention, the
functionalized particulate bicarbonate comprises the bicarbonate
ingredient and the at least one additive in powder form.
[0178] For certain applications it is preferred that the
functionalized particulate bicarbonate of the present invention
contains sodium bicarbonate as particles which are coated with a
coating of additive. Such coating can improve some properties of
the functionalized particulate bicarbonate. The additive in such
instance may be termed a "coating agent". The additive as coating
agent shall mean that this additive is able to cover, partly or
completely, the surface of particles of bicarbonate. The "coating
agent" is a different compound than bicarbonate ingredient from
which the core of the particles are made of
[0179] For certain applications, it is envisioned that the
functionalized particulate bicarbonate of the present invention
contains sodium bicarbonate co-milled with one additive. Such
co-milling with the additive can improve some properties of the
functionalized particulate bicarbonate.
[0180] For certain applications, the functionalized particulate
bicarbonate of the present invention contains sodium bicarbonate as
particles which are functionalized with more than one additive. The
functionalization of the sodium bicarbonate particles may be
carried out simultaneously with the additives using one
functionalization method, or may be carried out sequentially using
one additive with one functionalization method and then another
additive with the same or different functionalization method. For
example, sodium bicarbonate particles may be first functionalized
with a first additive, and then these first-functionalized
particles are again functionalized with a second additive (the
second additive having the same composition or a different
composition as the first additive, preferably having a different
composition). The methods used for subsequent functionalizations
may be the same, but preferably are different. The (first and
second) functionalization methods are preferably selected from the
group consisting of extrusion, co-grinding, and spray coating. For
example, the first functionalization method may comprise or consist
of co-grinding or extrusion, and the second functionalization
method may comprise or consist of extrusion, co-grinding, or spray
coating. Preferably, the first functionalization method may
comprise or consist of co-grinding, and the second
functionalization method may comprise or consist of extrusion.
[0181] For certain applications, the functionalized particulate
bicarbonate of the present invention contains sodium bicarbonate as
particles which are functionalized with one additive, but the
additive is not added all at once, but added sequentially in
several portions. For example, bicarbonate particles may be first
functionalized with a first portion of the additive, and then these
first-functionalized bicarbonate particles are again functionalized
with a second portion of the same additive. The methods used for
functionalization may be the same or may be different. For example,
the (first and second) functionalization methods are preferably
selected from the group consisting of extrusion, co-grinding, and
spray coating. Preferably, the first functionalization method may
comprise or consist of co-grinding, and the second
functionalization method may comprise or consist of extrusion.
[0182] For certain applications, it may be preferred that the
functionalized particulate bicarbonate of the present invention
contains sodium bicarbonate as particles which are coated with a
coating of a first additive, and then these coated particles are
co-milled with a second additive (the second additive having the
same composition or a different composition as the first
additive).
[0183] For certain applications, the production of a fine cellular
foam, so to produce a certain small amount of gas at one place,
might be desirable. In order to improve the cellular foam structure
it can be suitable that the functionalized particulate bicarbonate
has a characteristic particle size and particle size distribution.
The D.sub.50 term is designating the diameter for which 50% by
weight of the particles have a diameter less than or equal to
D.sub.50 (weight average diameter). The D.sub.10 term is
designating the diameter for which 10% by weight of the particles
have a diameter less than or equal to D.sub.10. The D.sub.90 term
is designating the diameter for which 90% by weight of the
particles have a diameter less or equal to D.sub.90.
[0184] The functionalized particulate bicarbonate may have
advantageous properties, such as a low particle size preferably
with a low span. The span of the particle size distribution is as
known in the art defined as the ratio (D.sub.90-D.sub.10)/D.sub.50.
The span may range from about 1 to about 6, such as from about 1 to
about 3. In one embodiment the span may be lower than 6, preferably
lower than 4, more preferably lower than 3. In one embodiment the
span may be higher than 1, preferably higher than 2. In another
embodiment the span may be lower than 1.8, more preferably at most
1.7 in particular at most 1.6, e.g. at most 1.5.
[0185] Preferably, the particles of the functionalized particulate
bicarbonate have a particle size distribution of D.sub.50 of at
most 250 .mu.m, preferably at most 100 .mu.m, more preferably at
most 60 .mu.m, yet more preferably at most 40 .mu.m, or at most 30
.mu.m, or at most 25 .mu.m.
[0186] In some embodiments, the particles of the functionalized
particulate bicarbonate have a particle size distribution of
D.sub.50 of more than 1 .mu.m, preferably more than 2 .mu.m, more
preferably more than 5 .mu.m, yet more preferably at least 8 .mu.m.
This functionalized particulate bicarbonate is termed
"functionalized micron-sized bicarbonate".
[0187] In some embodiments, the particles of the functionalized
particulate bicarbonate have a D.sub.10 in the range of 1 .mu.m-160
.mu.m, preferably in the range of 1 .mu.m-10 .mu.m, more preferably
in the range of 2 .mu.m-10 .mu.m, yet more preferably in the range
of 4 .mu.m-8 .mu.m, in particular 5 .mu.m-6 .mu.m.
[0188] In some embodiments, the particles of the functionalized
particulate bicarbonate have a D.sub.90 in the range of from 20
.mu.m to 450 .mu.m, preferably from 30 .mu.m to 200 .mu.m, more
preferably from 30 .mu.m to 165 .mu.m, in particular from 30 .mu.m
to 100 .mu.m.
[0189] The weight-average diameter D.sub.50, as well as D.sub.10
and D.sub.90 values can be measured by laser diffraction and
scattering on a Malvern Mastersizer S particle size analyser using
an He--Ne laser source having a wavelength of 632.8 nm and a
diameter of 18 mm, a measurement cell equipped with a backscatter
300 mm lens (300 RF), and MS 17 liquid preparation unit, and an
automatic solvent filtration kit ("ethanol kit") using ethanol
saturated with bicarbonate (wet method).
[0190] The functionalized particulate bicarbonate shows excellent
CO.sub.2 release properties. As determined by TGA analysis, the
maximum loss temperature of the functionalized particulate
bicarbonate is preferably higher than the non-functionalized
bicarbonate without additive. The CO.sub.2 release of the
functionalized particulate bicarbonate typically has its maximum at
a temperature of at least 130.degree. C., preferably at a
temperature of at least 135.degree. C., more preferably at a
temperature of at least 140.degree. C., even more preferably at a
temperature of at least 145.degree. C., and particularly preferably
at a temperature of at least 155.degree. C.
[0191] As determined by Differential Scanning calorimetry (DSC)
thermal analysis, the functionalized particulate bicarbonate
preferably has the maximum peak temperature higher than the
non-functionalized bicarbonate without additive. The DSC maximum
peak temperature of the functionalized particulate bicarbonate may
be at least 140.degree. C., preferably at least 145.degree. C.,
more preferably at least 150.degree. C., even more preferably at a
temperature of at least 155.degree. C., and particularly preferably
at a temperature of at least 160.degree. C.
Functionalized Nano-Sized Bicarbonate
[0192] In some embodiments, the particles of the functionalized
particulate bicarbonate have a particle size distribution of
D.sub.50 of at most 1 .mu.m, preferably less than 1 .mu.m. This
functionalized particulate bicarbonate is termed "functionalized
nano-sized bicarbonate".
[0193] In the instance when the functionalized particulate
bicarbonate is based on nano-sized bicarbonate particles, it is
preferred that the bicarbonate nano-sized particles are formed
before functionalization. Techniques such as wet grinding with a
solvent, micronisation and dry nanogrinding would be effective. Use
of mills such as tumbler ball mills, planetary ball mills (for
example available from Retch) or jet mills (for example available
from Alpine) is suitable for making nano-sized bicarbonate
particles. Ball milling involves decomposition of bulk solid
materials into nanoscale regimes using a mechanical force. The
reduction of particle size by high energy ball milling is termed as
mechanical milling. Since milling a powder of bicarbonate powder to
nanosize level generates quite a lot of heat, it is recommended to
cool during the milling. Additionally, to facilitate the milling to
nanosize level, it may be recommended to use a lubricant.
[0194] Additionally, to prevent particles from re-agglomerating
during milling or after exiting the mill, it may be recommended to
use a surfactant. These nano-sized particles have strong tendency
to agglomerate owing to having large specific surface area.
Surfactants may play an important role to prevent this close
contact of the nano-sized particles by providing steric barrier and
reducing surface tension. The surfactant molecules form a thin
organic layer around the newly formed surfaces to protect the
exposed surface from cold wielding when they come into contact with
another surface during the milling process or when they exit the
mill. A suitable surfactant may include a polymer such as
poly(acrylic acid, sodium salt), or a fatty acid or ester thereof,
such as oleic acid, stearic acid, oleic acid or oleylamine,
palmitic acid, mysteric acid, undecanoic acid, octanoic acid,
and/or valeric acid.
[0195] Because the functionalization adds another compound
(additive) to the nanosized bicarbonate core particles, it is
recommended to select a technique for additive
deposition/incorporation (techniques being described in more detail
below) which would not significantly increase the size of the
initial bicarbonate core particles. It would be preferred for
example for the particulate bicarbonate initially having a D50 of 1
.mu.m or less before functionalization to generate after
functionalization a functionalized particulate bicarbonate still in
the nanosized range with a D50 of at most 1 .mu.m or less. It is
though acceptable in some instances that the functionalized
particulate bicarbonate starting from nanosized bicarbonate core
particles may reach a D50 of 2 .mu.m or less after
functionalization.
Additive in Functionalized Particulate Bicarbonate
[0196] The additive in the functionalized particulate bicarbonate
may comprise or consist of, as non-limiting examples, at least one
following compound: [0197] one or more polymers; [0198] one or more
amino acids, any derivative thereof, and salts thereof; [0199] one
or more inorganic salts; [0200] one or more oils; [0201] one or
more fats; [0202] one or more resin acids, any derivative thereof,
and salts thereof; [0203] one or more fatty acids, any derivative
thereof, and salts thereof; [0204] a carboxylic or polycarboxylic
acid, derivative thereof (such as esters), or salts thereof; [0205]
one or more soaps; [0206] one or more waxes; or [0207] any
combinations thereof.
[0208] In some embodiments, the additive may comprise or consist of
a polymer selected from the group consisting of polyvinylalcohol,
polyglycol, polysaccharide, poly(meth)acrylic acid, poly(acrylic
acid co-maleic acid, polyethylenenimine, polyvinylpyrrolidone,
N-2(-Hydroxypropyl) methacrylamide, polyoxyalkylenes and
derivatives thereof including polyethylene glycol, and combinations
thereof.
[0209] In some embodiments, the additive may comprise or consist of
a polysaccharide selected from the group consisting of hydrolyzed
starch, carboxymethylcellulose, alginic acid and its salt, arabic
gum, carrageenan; guar gum, locust bean gum, xantham gum and
combinations thereof.
[0210] In some embodiments, the additive may comprise or consist of
an amino acid, derivative thereof or salt thereof selected from the
group consisting of casein, gelatin, glycine, proline,
hydroxyproline, glutamic acid, alanine, arginine, aspartic acid,
lysine, pectin, serine, leucine, valine, phenylalanine, threonine,
isoleucine, hydroxylysine, methionine, histidine, tyrosine and
combinations thereof.
[0211] In some embodiments, the additive may comprise or consist of
an inorganic salt selected from the group consisting of silicates
(e.g., sodium silicate), NaCl, KCl, MgCl2, sodium phosphate,
borates, nitrates, nitrites, sulfates, sulfites and combinations
thereof.
[0212] In some embodiments, the additive may comprise or consist
of: [0213] an amino acid, derivative thereof, or salt thereof,
[0214] a polysaccharide (such as hydrolyzed starch, gums,
carboxymethylcellulose), [0215] a resin acid, derivative thereof,
or salt thereof, [0216] a fatty-acid, derivative thereof (such as
esters), or salt thereof, [0217] a carboxylic or polycarboxylic
acid, derivative thereof (such as esters), or salts thereof; or
[0218] any combination thereof.
[0219] In some embodiments, the additive may comprise or consist
of: [0220] a polymer (such as polyoxyalkylenes and derivatives
thereof including polyethylene glycols, poly(meth)acrylates and
derivatives thereof, polyvinylalcohol and polysaccharides,
including modified, in particular hydrolyzed starch, maltodextrin
and gum arabic), [0221] an amino acid, derivative thereof, or salt
thereof (such as leucine), [0222] an oil (such as epoxidized soy
bean oil), [0223] a resin acid, derivatives thereof, or salt
thereof (such as rosin acid), [0224] a fatty acid, derivatives
thereof, or salt thereof (such as stearic acid, lauric acid,
linoleic acid and glycerol mono stearate), [0225] a wax (such as
bees wax and carnauba wax), or, [0226] any combination thereof.
[0227] In some embodiments, the additive may comprise or consist of
a compound which is capable of liberating CO2 and which is also
used for functionalizing the particulate bicarbonate. This additive
may be considered as a secondary blowing agent in the
functionalized particulate bicarbonate. Not only this additive
would provide an increase in the CO2 generation when the
functionalized particulate bicarbonate is used as an endothermic
blowing agent, but also this additive would protect the bicarbonate
core from premature CO2 release by protecting its surface (or part
thereof). This CO2-liberating additive may be a carboxylic or
polycarboxylic acid, derivative thereof (such as esters), or salts
thereof.
[0228] Suitable carboxylic acids include those of the formula:
HOOC--R--COOH where R is an alkylene group of 1 to about 8 carbon
atoms which may also be substituted by one or more hydroxy groups
or keto groups and may also contain unsaturation. Also included are
esters, salts and half salts.
[0229] A preferred CO2-liberating additive may include at least one
of: [0230] fumaric acid, [0231] tartaric acid, or [0232] citric
acid, citrates (such as sodium hydrogen citrate, disodium citrate),
or esters of citric acid.
[0233] Esters of citric acid may include tributyl citrate, triethyl
citrate, tri-C12-13 alkyl citrate, tri-C14-15 alkyl citrate,
tricaprylyl citrate, triethylhexyl citrate, triisocetyl citrate,
trioctyldodecyl citrate and triisostearyl citrate, isodecyl citrate
and stearyl citrate, dilauryl citrate, and/or ethyl citrates
(mixture of tri-, di- and monoesters), preferably tributyl citrate,
triethyl citrate, isodecyl citrate, or triethylhexyl citrate.
[0234] A more preferred CO2-liberating additive comprises or
consists of citric acid, any ester thereof, or any salt
thereof.
[0235] In some embodiments, the additive excludes citric acid,
esters thereof, or salts thereof.
[0236] In some embodiments, the additive may comprise or may
consist of an amino acid, a derivative thereof, or a salt
thereof.
[0237] Generally, the amino acids are compounds as known in the art
composed of an amino group and a carboxylic acid functional group.
An amino group is, in accordance with IUPAC nomenclature a compound
formally derived from ammonia (NH.sub.3) by replacing one, two or
three hydrogen atoms by hydrocarbyl groups, and having the general
structures RNH.sub.2 (primary amines), R.sub.2NH (secondary amines)
or R.sub.3N (tertiary amines). In accordance with IUPAC
nomenclature, derivatives of ammonium compounds
(NH.sub.4.sup.+)Y.sup.- in which all four of the hydrogens bonded
to the nitrogen have been replaced with hydrocarbyl groups, are
considered as quaternary ammonium compounds which are not amines.
That is, in the amino acids as used in accordance with the present
invention the amine group, preferably the a-amine group, is a
RNH.sub.2, R.sub.2NH or R.sub.3N residue but not an NR.sub.4.sup.+
residue. Preferably, quaternary ammonium compounds comprising a
carboxylic acid group are not used as amino acid additive in
accordance with the present invention.
[0238] In a preferred embodiment of the invention, the amino acid
used as additive is a .beta.-amino acid or an .alpha.-amino acid,
most preferred an .alpha.-amino acid. .alpha.-amino acids generally
have a chemical structure according to formula (I)
##STR00001##
or a salt thereof. Residue R may be hydrogen, or an alkyl or an
optionally substituted aryl or an optionally substituted heteroaryl
group. Preferably, residue R is a C.sub.1-C.sub.10 alkyl group, in
particular a C.sub.1-C.sub.6 alkyl group. Most preferably R is a
methyl, propan-2-yl (isopropyl), butan-2-yl, or
2-methyl-propan-1-yl.
[0239] In a preferred embodiment, the .alpha.-amino acid is
selected from the group consisting of positively charged amino
acids, such as arginine, histidine, and lysine, negatively charged
amino acids such as aspartic acid or glutamic acid, polar uncharged
amino acids such as serine, threonine, asparagine or glutamine, or
cysteine, selenocysteine, glycine and proline. Particular preferred
are amino acids with hydrophobic side chain, such as alanine,
valine, isoleucine, leucine, methionine, phenylalanine, tyrosine
and tryptophan. Most preferred amino acids used as additives are
valine, isoleucine and leucine, leucine being most preferred.
[0240] .alpha.-amino acids are chiral compounds. Generally, both
racemic mixtures of the both enantiomeres can be used, as well as
compositions enriched in one enantiomer, e.g. the D- or the
L-enantiomer. Preferably, racemic mixtures of the amino acids may
be used in accordance with one embodiment of the present
invention.
[0241] Suitable derivatives of amino acids are for example esters,
such as esters comprising a hydroxyalkyl residue, in particular a
hydroxy C.sub.1-20 alkyl residue. Alternatively or additionally the
amino acid derivative may be an amide. Suitable salts are for
example alkali metal and alkali earth metal salts or salts formed
between an acid, such as an inorganic acid or a carboxylic acid
with the amino group of the amino acid.
[0242] The amino acid should be present in the functionalized
particulate bicarbonate according to the present invention in the
amount of at least 0.02% by weight, preferably at least 0.05% by
weight, in particular at least 0.1% by weight. More than 10% by
weight of the amino acid in the functionalized particulate
bicarbonate is disadvantageous for cost reasons. Preferably, at
most 8% by weight, more preferably at most 6% by weight, in
particular at most 5% by weight of the amino acid are present in
the functionalized particulate bicarbonate in accordance with one
embodiment of the present invention.
[0243] The preferred amino acid used as additive in the
functionalized particulate bicarbonate is leucine. Leucine may for
example be present in the functionalized particulate bicarbonate in
an amount of 0.02% by weight to 5% by weight, preferably in an
amount of 0.05% by weight to 2% by weight, more preferably in an
amount of 0.05% by weight to 0.5% by weight.
[0244] In one embodiment the particulate bicarbonate being
functionalized with an amino acid, in particular leucine, is
prepared by spray-drying.
[0245] In additional or alternate embodiments, the additive in the
functionalized particulate bicarbonate may comprise or consist of a
resin acid, a derivative thereof, or a salt thereof.
[0246] Generally, the resin acid to be used as additive in the
functionalized particulate bicarbonate is one of the resin acids as
known in the art. The resin acids refer to mixtures of related
carboxylic acids, preferably abietic acid, found in tree resins.
Typically, resin acids have the basic skeleton of three fused rings
with an empirical formula C.sub.19H.sub.29COOH. Preferred the resin
acid is a tricyclic diterpene carboxylic acid, more preferable
belonging to the abietane diterpene group. Preferred resin acids
are abietic-type acids, e.g. selected from the group consisting of
abietic acid (abieta-7,13-dien-18-oic acid), neoabietic acid,
dehydroabietic acid, and palustric acid. Also suitable are
pimaric-type acids, selected from the group consisting pimaric acid
(pimara-8(14),15-dien-18-oic acid), levopimaric acid, or isopimaric
acid. Such acids are available from natural sources or via chemical
synthesis as e.g. known from US 2014/0148572 A1.
In the context of the present invention "abietic acid" is also
referred to as "rosin acid".
[0247] A derivative containing resin acids that may be used in
accordance with the present invention is tall oil. Tall oil (also
called liquid rosin) is obtained as a by-product of the Kraft
process of wood pulp manufacture. Crude tall oil contains rosin,
resin acids (mainly abietic acids and its isomers), fatty acids
(mainly palmetic, and oleic), fatty alcohols, sterols and alkyl
hydrocarbon derivatives. Most preferred abietic acid, pimaric acid
and their salts, in particular the sodium salts, respectively are
used as additive in accordance with the present invention.
[0248] The resin acid, derivative thereof, or salt thereof should
be present in the functionalized particulate bicarbonate according
to the present invention in an amount of at least 0.02% by weight,
preferably at least 0.05% by weight, in particular at least 0.1% by
weight. The resin acid, derivative thereof, or salt thereof, such
as rosin acid, may for example be present in an amount from 0.02%
by weight to 25% by weight, preferably from 0.02% by weight to 20%
by weight or from 0.1% by weight to 11% by weight, such as from
0.5% by weight to 10% by weight.
[0249] The preferred resin acid used as additive in the
functionalized particulate bicarbonate is rosin acid, derivative
thereof, or salt thereof. The rosin acid, derivative thereof, or
salt thereof may for example be present in an amount from 1% by
weight to 25% by weight, preferably from 5% by weight to 20% by
weight in the functionalized bicarbonate.
[0250] In yet additional or alternate embodiments, the additive in
the functionalized particulate bicarbonate may comprise or consist
of a fatty-acid, derivative thereof (such as esters), or a salt
thereof.
[0251] Fatty acids as used as additive in the present invention are
those fatty acids as known in the art, i.e., a carboxylic acid with
an aliphatic residue, which is either a saturated or unsaturated.
Preferred, the fatty acid is a compound according to formula
(II)
R--COOH (II)
wherein R is a saturated or unsaturated C.sub.6-C.sub.18 alkyl
group, preferably a C.sub.12-C.sub.18 group, such as a
C.sub.12-C.sub.16 alkyl group. The fatty acids may be used in form
of their salts, in particular sodium or potassium salts, most
preferably sodium salt. Even more preferred residue R is a
C.sub.16-C.sub.18 alkyl group, most preferred, the fatty acid is
palmetic acid, linoleic acid, lauric acid or stearic acid, the
latter being most preferred.
[0252] Examples of fatty acid derivatives are glycerides.
Glycerides are esters formed from glycerol and fatty acids, in
particular glycerol mono, di and tri fatty esters.
[0253] The preferred fatty acid used as additive in the
functionalized particulate bicarbonate is stearic acid, an ester
thereof, or a salt thereof. The more preferred fatty acid used as
additive in the functionalized particulate bicarbonate is stearic
acid, a stearate salt, or an ester of stearic acid, such as its
ester with glycerol, such as tristearin, or glyceryl tristearate,
which is a triglyceride derived from three units of stearic acid.
Another preferred additive is glycerol mono stearate.
[0254] The fatty acid, derivative thereof, or salt thereof should
be present in the functionalized particulate bicarbonate according
to the present invention in an amount of at least 0.02% by weight,
preferably at least 0.05% by weight, in particular at least 0.1% by
weight. In certain embodiments the fatty acid, derivative thereof,
or salt thereof may be present in the functionalized particulate
bicarbonate in an amount of from 0.02% by weight to 30% by weight,
preferably from 0.1% by weight to 10% by weight, more preferably
from 0.5% by weight to 7% by weight.
[0255] In some embodiments, the additive may exclude stearic acid,
an ester thereof, or salts thereof.
[0256] In yet more additional or alternate embodiments, the
additive may comprise or consist of a polymer, such as a polymer
selected from the group consisting of polyvinylalcohol, polyglycol,
polysaccharide, poly(meth)acrylic acid, poly(acrylic acid co-maleic
acid, polyethylenenimine, polyvinylpyrrolidone, N-2(-Hydroxypropyl)
methacrylamide, polyoxyalkylenes and derivatives thereof including
polyethylene glycols, and combinations thereof.
[0257] The polymer may be a natural or synthetic polymer. Natural
polymers are polymers being from natural sources, such as starch
and arabic gum. Natural polymers may also be modified, such as
hydrolyzed starch.
[0258] Synthetic polymers are for example poly(meth)acrylates and
derivatives thereof, polyoxyalkylenes and derivatives thereof
including polyethylene glycols, and polyvinylalcohols. A preferred
polyoxyalkylene derivative is for example a polymer offered under
the trade name BYK 3155 by BYK-Chemie GmbH. Meth-/acrylic polymers
may for example be anionic polymers with methacrylic acid as
functional groups, cationic polymers with methylaminoethyl
methacrylates as functional groups, meth-/acrylate copolymers with
trimethyl-aminoethyl-methacrylate as functional groups and neutral
polymers of meth-/acrylates which are available from Evonik under
the trade name Eudragit.RTM.. Suitable Eudragit.RTM. grades are for
example grades L, S, FS, E, RL, RS, NE and NM. Preferred are
Eudragits.RTM. of grade RL, in particular Eudragit.RTM. RL 30D.
[0259] Polyethylene glycols are available in a wide range of
different molecular weights. In one embodiment of the present
invention low molecular weight polyethylene glycols having a
molecular weight below 1000 g/mol can be used, preferably a
polyethylene glycol having a molecular weight in the range of from
200 to 600 g/mol, such as in the range of from 300 to 500 g/mol,
preferably PEG400. In another embodiment of the present invention a
high molecular weight polyethylene glycol having a molecular weight
of 1000 g/mol or above may be employed. Preferably the high
molecular weight polyethylene glycol has a molecular weight of from
1000 to 10000 g/mol, more preferably from 2000 to 8000 g/mol, such
as PEG4000.
[0260] In some embodiments, when a polysaccharide is used as
additive in the functionalized particulate bicarbonate, the
polysaccharide additive may be at least one polysaccharide selected
from the group consisting of hydrolyzed starch,
carboxymethylcellulose, alginic acid and salts thereof, arabic gum,
carrageenan, guar gum, locust bean gum, xantham gum, and
combinations thereof.
[0261] The additive in the functionalized particulate bicarbonate
may comprise or consist of a polysaccharide selected from the group
consisting of: [0262] guar gums and their derivatives, in
particular hydroxypropyl guar (such as Jaguar HP-105); [0263]
alginic acid and its salts, such sodium, calcium or copper (e.g.,
Kaltostat, Calginat, Landalgine, Kalrostat, Kelacid, Vocoloid,
Xantalgin); and [0264] carboxymethylcellulose (e.g., Aquaplast,
Carmethose, CELLOFAS, Cellpro, Cellugel, Collowel, Ethoxose,
Orabase, Lovosa).
[0265] In another embodiment the additive of the functionalized
particulate bicarbonate may comprise or consist of a modified, in
particular hydrolyzed starch or a compound comprising such starch.
Particularly preferred additives of this class are hydrolyzed
starch, arabic gum and maltodextrin, maltodextrin being
particularly preferred. The polymer should be present in the
functionalized particulate bicarbonate according to the present
invention in an amount of at least 0.02% by weight, preferably at
least 0.05% by weight, more preferably at least 0.1% by weight. In
particular the hydrolyzed starch, arabic gum, maltodextrin,
polyoxyalkylene derivatives including polyethylene glycols,
poly(meth)acrylate, and polyvinylalcohol may for example be present
in an amount of between 0.02% by weight to 40% by weight, more
preferably from 0.1% by weight to 35% by weight, even more
preferably from 1% by weight to 20% by weight, such as from 2% by
weight to 10% by weight.
[0266] Oils used as additive in the present invention may be
organic oils or mineral oils which may be of animal, vegetable, or
petrochemical origin. Suitable oils are for example olive oil,
maize oil, sunflower oil and soybean oil.
[0267] The oil may be chemically modified, such as epoxidized. A
preferred oil is epoxidized soybean oil. The oil should be present
in the functionalized particulate bicarbonate according to the
present invention in an amount of at least 0.02% by weight,
preferably at least 0.05% by weight, in particular at least 0.1% by
weight. In preferred embodiments the oil can be present in the
functionalized particulate bicarbonate in an amount of from 0.1% by
weight to 10% by weight, more preferably from 1% by weight to 7% by
weight.
[0268] In a further embodiment the additive in the functionalized
particulate bicarbonate is a wax, such as bees wax or carnauba
wax.
[0269] The wax should be present in the functionalized particulate
bicarbonate according to the present invention in the amount of at
least 0.02% by weight, preferably at least 0.05% by weight, in
particular at least 0.1% by weight. The wax can for example be
present in an amount of from 1% by weight to 30% by weight,
preferably from 5% by weight to 25% by weight.
[0270] Additional information on particular properties of
functionalized particulate bicarbonate can be found in
WO2016/102591A1 by SOLVAY SA when the additive comprises or
consists of an amino acid or salt thereof; in EP3037388A1 by SOLVAY
SA when the additive comprises or consists of a resin acid or fatty
acid as additive.
Method of Making Functionalized Particulate Bicarbonate
[0271] The present invention further relates to a method for making
functionalized particulate bicarbonate.
[0272] The functionalized particulate bicarbonate may be prepared
from a solution containing a bicarbonate ingredient or directly
from an already-formed particulate bicarbonate.
[0273] The bicarbonate ingredient or particulate bicarbonate may
comprise or consists essentially of ammonium bicarbonate, sodium
bicarbonate, potassium bicarbonate, or mixtures thereof, in
particular the bicarbonate ingredient or particulate bicarbonate
comprises or consists essentially of sodium bicarbonate. The
bicarbonate ingredient or particulate bicarbonate preferably
comprises at least 80 wt % of sodium bicarbonate.
[0274] The functionalized particulate bicarbonate according to one
aspect of the present invention may be obtained by encapsulation or
coating processes.
[0275] In particular, another aspect of the present invention
relates to a process for preparing functionalized particulate
bicarbonate, preferably a functionalized particulate alkali metal
bicarbonate as described above according to the invention by at
least one of the following processes: [0276] by spray-drying (also
known as atomization), wherein the additive is dissolved in the
bicarbonate-containing solution. [0277] by grinding or co-grinding
(also known as milling or co-milling) with the additive(s) in
emulsion or powder form; [0278] by spray coating and granulation
within a fluidized bed, [0279] by spray agglomeration within a
fluidized bed, [0280] by spray chilling (e.g., spray cooling, spray
freezing), [0281] by roller compaction, and/or [0282] by extrusion,
including simultaneous mixing/extrusion.
[0283] Spray-drying or drying by atomization is a drying technique.
This method comprises spraying the product to be dried, which is in
the form of a solution (or a suspension) in a stream of hot gas, so
as to obtain a powder in a few seconds or fractions of seconds. The
separation of a solution into fine droplets gives rise to a large
material transfer surface and it leads to rapid evaporation of the
solvent of the solution used.
[0284] Suitable apparatus for spray-drying are known in the art,
and generally comprise several modules: a module comprising a
circuit for storing and atomizing the solution comprising equipment
for atomizing or spraying the solution, a module for the
preparation of hot gas and its transfer to a drying chamber where
it comes into contact with the sprayed solution, a drying chamber
where the sprayed solution is evaporated and the particles are
formed, and a module for collecting the particles, generally
comprising a cyclone and/or a suitable filter.
[0285] Generally, the equipment for atomizing or spraying the
solution is a compressed gas sprayer or a dispersion turbine. Also
ultrasound nozzles can be used for spraying the solution.
[0286] In the spray-drying process of the invention generally an
aqueous solution of the bicarbonate is used. While other polar
solvents or mixtures of polar solvents, for examples mixtures of
water and ethanol, in which the additive is soluble, may be used,
water is the preferred solvent.
[0287] In the spray-drying method of the present invention the
aqueous solution to be spray-dried comprises 1 to 10% by weight of
the bicarbonate ingredient. The bicarbonate ingredient in the
solution is preferably an alkali metal bicarbonate. The solution to
be spray-dried further comprises 1 to 10,000 ppm of an additive or
salt thereof. The additive used is preferably one of those as
described above for the particulate bicarbonate of the present
invention. In preferred embodiments, the content of the additive in
the solution to be spray-dried is 1 to 5,000 ppm, more preferred 1
to 3,000 ppm, in particular 10 to 2,000 ppm, e.g. 50-1,000 ppm of
additive per kg of solution to be spray-dried. Generally, the
aqueous solution comprises at least 1 mg, preferably at least 5 mg,
more preferably at least 10 mg, even more preferred at least 100 mg
of the additive per kg of aqueous solution. Generally, the aqueous
solution comprises at most 2,000 mg, preferably at most 1,500 mg,
more preferably at most 1,200 mg of the additive per kg of aqueous
solution. In case of salts, weight percentages are given based on
the free base/acid.
[0288] Generally, in the spray-drying process in the method for
making functionalized particulate bicarbonate, the aqueous solution
comprises at least or more than 1%, preferably at least or more
than 2%, more preferably at least or more than 3%; even more
preferably at least or more than 4%, in particular at least or more
than 5% by weight of the bicarbonate ingredient. Preferably, the
bicarbonate ingredient comprises or consists essentially of sodium
bicarbonate and/or potassium bicarbonate, in particular comprise or
consists essentially of sodium bicarbonate. A high concentration of
the bicarbonate ingredient in the aqueous solution is detrimental
as leading to high speed plugging of the spraying or atomizing
device. Therefore it is generally recommended that the aqueous
solution comprises at most or less than 10% by weight, preferably
at most or less than 8% by weight, more preferably at most or less
than 6% by weight of the bicarbonate ingredient, in particular
sodium bicarbonate. Preferably, the bicarbonate-containing solution
is an aqueous solution comprising 1%-10%, advantageously 3%-8%,
more advantageously 4%-8% by weight, such as 4%-6% by weight of the
bicarbonate ingredient, in particular sodium bicarbonate.
[0289] The drying with a hot gas breaks part of the alkali metal
bicarbonate down into the form of sodium carbonate, CO.sub.2 and
water. In one advantageous embodiment of the present invention, the
spray-drying is carried out in a gas comprising at least 5%,
advantageously at least 10%, more advantageously at least 20%, and
even more advantageously at least 30% of CO.sub.2 by volume on a
dry gas bases. This enables to limit the bicarbonate decomposition
into carbonate solid and CO.sub.2 gas and water vapor. Generally,
the spray-drying is carried out with a gas preheated between
40.degree. C. and 220.degree. C. Advantageously the spray-drying is
carried out in a spray-drying chamber and wherein the gas is
preheated before being introduced into the spray-drying chamber at
least 40.degree. C., preferably at least 50.degree. C., more
preferably at least 60.degree. C., even more preferably at least
70.degree. C. Also advantageously, the gas is preheated before
being introduced into the spray-drying chamber at most 220.degree.
C., preferably at most 200.degree. C., more preferably at most
180.degree. C., even more preferably at most 130.degree. C.
[0290] It is preferable for the temperature of the gas after the
spray-drying operation to be at most 80.degree. C., advantageously
at most 70.degree. C. and more advantageously at most 60.degree.
C.
[0291] In one embodiment in the method for making functionalized
particulate bicarbonate, the aqueous solution is preheated to a
temperature of at least 20.degree. C. and preferably at most
80.degree. C. before being sprayed during the spray-drying
operation. In one particular embodiment, the aqueous solution is
preheated to a temperature of at least 20.degree. C. and at most
25.degree. C. before being sprayed during the spray-drying
operation.
[0292] The method for making functionalized particulate bicarbonate
according to the present invention may comprise co-grinding of the
bicarbonate ingredient in the presence of the additive, such as in
the presence of 0.02 to 10 parts by weight of an additive per 100
parts per weight of the substance undergoing co-grinding. The
bicarbonate ingredient and the additive are preferably as defined
above.
[0293] In the process for preparing the functionalized particulate
bicarbonate by co-grinding, all suitable grinding procedure as
known in the art can be used.
[0294] Typical devices include impact mills, which are mills in
which the material be milled as subjected to the impact of moving
mechanical part and that have the effect of fragmenting the
particles of the material. Impact mills are well-known in the fine
milling art. Such mills include hammer mills, spindle mills,
attritor mills, jet mills, ball mills, such as planetary ball
mills, and cage mills. Such mills are e.g. manufactured and
available by Grinding Technologies and System SRL or by Hosokawa
Alpine AG. Most preferred, an Alpine LGM 3 is used. In the process
for preparing the alkali metal bicarbonate particles, the alkali
metal bicarbonate is grinded in the presence of the additive, i.e.
the amino acid as defined above. Either the total amount of
bicarbonate and additive is added into the mill at once, followed
by milling or preferably the bicarbonate and the additive are fed
into the milling device at a constant rate. Suitable rates for the
bicarbonate are 50 kg/h to 500 kg/h, preferably 100 kg/h to 400
kg/h, e.g. about 150 kg/h. The amount of additive corresponds to
the weight ratio of the bicarbonate ingredient and additive used.
For examples, if the bicarbonate ingredient is co-grinded in the
presence of 1 part by weight of an additive, per 100 parts by
weight of the substance undergoing co-grinding, the feeding rate of
the additive is only 1% of the feeding rate of the bicarbonate
ingredient.
[0295] The amount of additive (e.g., polymer, resin acid, fatty
acid, carboxylic acid, amino acid, derivatives thereof, or salts
thereof, or combinations thereof) in the process for preparing the
functionalized particulate bicarbonate by co-grinding, is from 0.02
to 10 parts by weight per 100 parts by weight of the substance
undergoing co-grinding. Below 0.02 parts by weight, there is only
low efficacy of the additive. Using higher amounts than 10 parts by
weight of the additive is disadvantageous for cost reasons.
Preferred amounts are 0.2-8 parts by weight of the additive, more
preferred 0.5-5 parts by weight of additive, even more preferred
0.8-2 parts by weight of additive, in particular about 1 part by
weight of additive, each per 100 parts by weight of the substance
(typically the bicarbonate ingredient and the at least one
additive) undergoing co-grinding.
[0296] In some embodiment, the method for making functionalized
particulate bicarbonate according to the present invention may
comprise spray coating, for example within a fluidized bed. Spray
coating within a fluidized bed is a technique in which a powder
(solid particles of the bicarbonate ingredient) is fed into a
fluidization chamber. A gas fluidizes the powder from the chamber
bottom through a grid. A liquid which comprises the additive in
dissolved form, in a melted form, and/or in dispersed solid form
(for example a solution, an emulsion, a suspension, a melt, a melt
emulsion or a melt suspension) is sprayed into the fluidized powder
to apply a layer or coating onto particles.
[0297] In some embodiment, the method for making functionalized
particulate bicarbonate according to the present invention may
comprise spray granulation, for example within a fluidized bed. The
fluidized bed spray granulation is a method for making free-flowing
granulate from liquids. The liquid containing solids, such as
aqueous solutions, emulsions, suspensions, melts, melts emulsions
or melts suspensions, is sprayed into a fluidized bed system. The
solids are preferably bicarbonate particles. Due to the high heat
exchange the aqueous or organic solvent in the liquid evaporates
immediately, and the solids form small particles as starter cores.
These are sprayed with another liquid with contains the additive
(solution/suspension). A gas fluidizes the additive
solution/suspension sprayed into a chamber. After evaporation and
drying in the fluidized bed, the dried additive forms a hard
coating around the starter core. This step is continuously repeated
in the fluidized bed so that the granulate grows to form onion-like
or blackberry-like structures. An onion-like structure is obtained
from layer by layer coating. Alternatively, a defined volume of
suitable starter cores can be provided. In this option, the liquid
only serves as a vehicle for the solids that are being applied.
[0298] In some embodiment, the method for making functionalized
particulate bicarbonate according to the present invention may
comprise spray agglomeration, for example within a fluidized bed.
Spray agglomeration within a fluidized bed is a technique in which
a powder or a fine granulate is fed into a fluidization chamber. A
gas fluidizes the powder from the chamber bottom through a grid. A
liquid (either a solution, an emulsion, a suspension a melt, a melt
emulsion or a melt suspension), which acts as a binder, is sprayed
on the fluidized particles. Liquid bridges are created that form
agglomerates from the particles. Spraying continues until the
desired size of the agglomerates is reached.
[0299] In some embodiment, the method for making functionalized
particulate bicarbonate according to the present invention may
comprise spray chilling (or spray cooling, spray freezing). Spray
chilling is a technique in which a melt, a melt emulsion or a melt
suspension is sprayed into a fluidization chamber. A cold gas in
injected in the fluidization chamber. The solidification of solid
particles is achieved by the melt droplets losing heat to cold air
in the fluid bed.
[0300] In some embodiment, the method for making functionalized
particulate bicarbonate according to the present invention may
comprise roller compaction. Roller compaction is a technique in
which powder particles are made to adhere to each other by applying
a force onto the powder, which causes a considerable size
enlargement. The powder is compacted between two counter rotating
rolls to apply a force. The obtained briquettes, flakes or ribbons
are crushed out of the rolls to reach a desired particle size.
[0301] In some embodiment, the method for making functionalized
particulate bicarbonate according to the present invention may
comprise extrusion (or mixing extrusion). Extrusion (or mixing
extrusion) is a technique in which a powder or another material is
pushed through a die of a fixed cross-section. A screw, two screws
or a succession of paddles may help pushing the material through
mixing, degassing and homogenizing phases. Temperature control
along the distance allows for phase changing, melting,
crystallization, chemical reaction, coating or granulating the
materials.
Use of the Functionalized Particulate Bicarbonate
[0302] The present invention further relates to the use of the
herein described functionalized particulate bicarbonate as chemical
blowing agent for foaming [0303] a thermoplastic polymer, for
example PVC plastisol; or [0304] a polymer resin in an extrusion
process.
Chemical Blowing Agent
[0305] The present invention further relates to a chemical blowing
agent for foaming [0306] a thermoplastic polymer; or [0307] a
polymer resin in an extrusion process.
[0308] Thus, another aspect of the invention provides a chemical
blowing agent for foaming a thermoplastic polymer which comprises
the functionalized particulate bicarbonate as described in the
various embodiments herein, wherein the functionalized particulate
bicarbonate contains at least one additive as described in the
various embodiments herein.
[0309] In some embodiments, the chemical blowing agent for foaming
a thermoplastic polymer comprises a functionalized particulate
bicarbonate having a particle size D50 of 1000 nm or less.
[0310] In alternate embodiments, the chemical blowing agent for
foaming a thermoplastic polymer comprises a functionalized
particulate bicarbonate having a particle size D50 more than 1
micron and up to 250 .mu.m, preferably up to 30 .mu.m, or up to 25
.mu.m.
[0311] The additive in the functionalized particulate bicarbonate
may comprise or consist of, as non-limiting examples, at least one
following compound: [0312] one or more polymers; [0313] one or more
amino acids, any derivative thereof, and salts thereof; [0314] one
or more inorganic salts; [0315] one or more oils; [0316] one or
more fats; [0317] one or more resin acids, any derivative thereof,
and salts thereof; [0318] one or more fatty acids, any derivative
thereof, and salts thereof; [0319] a carboxylic or polycarboxylic
acid, derivative thereof (such as esters), or salts thereof [0320]
one or more soaps; [0321] one or more waxes; or [0322] any
combinations thereof.
[0323] Any particular embodiments for the functionalized
particulate bicarbonate and the additive(s) used for its
functionalization described herein are applicable here.
[0324] In some embodiments, the chemical blowing agent does not
contain a compound which liberates nitrogen gas during heating.
[0325] In some embodiments, the chemical blowing agent does not
contain a compound which liberates ammonia during heating.
[0326] In preferred embodiments, the chemical blowing agent is an
endothermic chemical blowing agent comprising the functionalized
particulate bicarbonate as described in the various embodiments
herein.
[0327] In preferred embodiments, the chemical blowing agent does
not contain an exothermic blowing agent.
[0328] In some embodiments, the chemical blowing agent comprises
the functionalized particulate bicarbonate and further comprises a
second compound as another blowing agent.
[0329] The second compound is preferably an endothermic blowing
agent.
[0330] The second compound preferably can liberate CO2 upon
heating. This second compound preferably increases the CO2
generation which is already formed by the decomposition of the
functionalized particulate bicarbonate upon heating.
[0331] This CO2-liberating second compound acting as blowing agent
may be a carboxylic or polycarboxylic acid, derivative thereof
(such as esters), or salts thereof.
[0332] Suitable carboxylic acids include those of the formula:
HOOC--R--COOH where R is an alkylene group of 1 to about 8 carbon
atoms which may also be substituted by one or more hydroxy groups
or keto groups and may also contain unsaturation. Also included are
esters, salts and half salts.
[0333] A preferred CO2-liberating second compound acting as blowing
agent may include at least one of: [0334] fumaric acid, [0335]
tartaric acid, or [0336] citric acid, citrates (such as sodium
hydrogen citrate, disodium citrate), or esters of citric acid.
[0337] Esters of citric acid may include tributyl citrate, triethyl
citrate, tri-C12-13 alkyl citrate, tri-C14-15 alkyl citrate,
tricaprylyl citrate, triethylhexyl citrate, triisocetyl citrate,
trioctyldodecyl citrate and triisostearyl citrate, isodecyl citrate
and stearyl citrate, dilauryl citrate, and/or ethyl citrates
(mixture of tri-, di- and monoesters), preferably tributyl citrate,
triethyl citrate, isodecyl citrate, or triethylhexyl citrate.
[0338] A more preferred CO2-liberating second compound acting as
endothermic blowing agent comprises or consists of citric acid,
esters thereof, or salts thereof.
Functionalized Second Compound in Blowing Agent Composition
[0339] It is also envisioned that the CO2-liberating second
compound in the blowing agent composition which supplements CO2
generation may also be in a functionalized particulate form. This
functionalized particulate second compound would comprise an
additive as described herein in relation to the functionalized
particulate bicarbonate. This functionalization of the particulate
second compound may also use one or more techniques as described
above in relation to the making of the functionalized particulate
bicarbonate.
[0340] In some embodiments, the endothermic blowing agent
comprises, or consists essentially of, or consists of: [0341] the
functionalized particulate bicarbonate, as described herein in the
various embodiments; and [0342] a functionalized particulate
carboxylic or polycarboxylic acid, derivative thereof (such as
esters), or salts thereof.
[0343] In particular embodiments, the endothermic blowing agent
comprises, or consists essentially of, or consists of: [0344] the
functionalized particulate bicarbonate, as described herein in the
various embodiments; and [0345] a functionalized particulate
carboxylic or polycarboxylic acid, derivative, or salt thereof,
selected from the group consisting of: fumaric acid, tartaric acid,
citric acid, salts thereof (such as sodium hydrogen citrate,
disodium citrate), esters thereof, and any combination thereof.
[0346] In some embodiments, the chemical blowing agent for foaming
a thermoplastic polymer comprises a functionalized particulate
bicarbonate and a functionalized particulate second compound (e.g.,
functionalized carboxylic or polycarboxylic acid, derivative, or
salt thereof), both having a particle size D50 of 1000 nm or
less.
[0347] In alternate embodiments, the chemical blowing agent for
foaming a thermoplastic polymer comprises a functionalized
particulate bicarbonate and a functionalized particulate second
compound (e.g., functionalized carboxylic or polycarboxylic acid,
derivative, or salt thereof), both having a particle size D50 more
than 1 micron and up to 250 microns, preferably up to 30
microns.
[0348] In yet alternate embodiments, the chemical blowing agent for
foaming a thermoplastic polymer comprises a functionalized
particulate bicarbonate having a particle size D50 of 1000 nm or
less and a functionalized particulate second compound (e.g.,
functionalized carboxylic or polycarboxylic acid, derivative, or
salt thereof) having a particle size D50 more than 1 micron and up
to 250 microns, preferably up to 30 microns.
[0349] In embodiments where the endothermic blowing agent comprises
the functionalized particulate bicarbonate and the functionalized
particulate second compound (e.g., functionalized carboxylic or
polycarboxylic acid, derivative, or salt thereof), the method for
making such blowing agent may contain the following steps: [0350]
A/ making the functionalized particulate bicarbonate using a first
additive (wherein the first additive is selected from those defined
herein); separately making the functionalized particulate second
compound using a second additive (wherein the second additive is
selected from those defined herein); mixing the functionalized
particulate bicarbonate and the functionalized particulate second
compound to make the endothermic blowing agent; or [0351] B/ mixing
the particulate bicarbonate and the particulate second compound
before functionalization to make a non-functionalized particulate
mixture; and functionalizing the non-functionalized particulate
mixture using at least one additive (as defined herein) to make the
endothermic blowing agent.
[0352] In the method A/, the first and second additives may be the
same or may be different. The techniques to make the functionalized
particulate bicarbonate and the functionalized particulate second
compound may be the same or may be different.
[0353] In the method B/, the additive and the technique for
functionalization of the particulate bicarbonate and the
particulate second compound is generally the same, thus resulting
in less flexibility in the making of the endothermic blowing agent.
However this method would be more cost effective.
Foamable Polymer Composition
[0354] Another aspect of the present invention relates to a
foamable polymer composition comprising
a) a polymer; b) the functionalized particulate bicarbonate used as
chemical blowing agent for foaming; and c) at least one polymer
additive.
[0355] The foamable polymer composition may optionally comprise a
functionalized particulate second compound used as supplemental
chemical blowing agent for foaming (as described herein).
[0356] The foamable polymer composition may optionally comprise a
foam stabilizer, such as a silicone based foam stabilizer.
[0357] The amount of the polymer in the foamable polymer
composition typically ranges between about 10 wt % (or 20 wt %) and
about 90 wt % based on the total weight of the foamable polymer
composition. The amount of polymer can be selected according to the
desired final characteristic of the foamable polymer
composition.
[0358] In one preferred embodiment according to the present
invention, the foamable polymer composition is in the form of a
plastisol. The term "plastisol" relates to a suspension of polymer
particles in a liquid plasticiser.
[0359] Preferably, the plastisol is a suspension of polyvinyl
chloride particles in a liquid plasticizer. The choice of the
plasticizer is not particularly limited and, therefore, commonly
employed plasticizers, such as dioctylphtalate or
1,2-cyclohexyldicarbonic acid diisononyl ester can be used for this
purpose.
[0360] The terms "polyvinyl chloride" intend to designate vinyl
chloride homopolymers as well as copolymers of vinyl chloride with
other ethylenically unsaturated monomers which are either
halogenated (chloroolefins like vinylidene chloride;
chloroacrylates; chlorinated vinylethers) or non halogenated
(olefins like ethylene and propylene; styrene; vinylethers like
vinyl acetate) monomers; as well as vinyl chloride copolymers with
acrylic and methacrylic acids; esters, nitriles and amides. Vinyl
chloride homopolymers and vinyl chloride copolymers containing
50-99 weight %, preferably 60-85 weight % of vinyl chloride are
preferred.
[0361] The amount of the plastisol in the foamable polymer
composition typically ranges between about 20 wt % and about 90 wt
% based on the total weight of the foamable polymer composition.
The amount of plastisol can be selected according to the desired
final characteristic of the foamable polymer composition.
[0362] The amount of the functionalized particulate bicarbonate in
the foamable polymer composition typically ranges from 5 to 15
parts per 100 parts by weight of polymer. For example, for a
foamable PVC polymer composition, the amount of the functionalized
particulate bicarbonate in the foamable PVC polymer composition
typically ranges from 5 to 15 parts per 100 parts by weight of PVC
resin, preferably from 6 to 12 parts per 100 parts by weight of PVC
resin; more preferably from 7 to 11 parts per 100 parts by weight
of PVC resin or from 8 to 10 parts per 100 parts by weight of PVC
resin.
[0363] The foamable polymer composition of the present invention
may contain further components, for instance, foam stabilizers; air
release agents; fillers or extenders (e.g., CaCO.sub.3 as a
filler), such as carbon black; other polymers and oils; curing
agents, such as sulfur compounds and various chemicals that act as
a part of a curing system, such as zinc oxide; antistatic agents;
biocides; colorants; coupling agents; fibrous reinforcements; flame
retardants; fungicides; heat stabilizers; lubricants; mold release
agents; plasticizers (e.g., DINP=di-isononyl phtalate);
preservatives; processing aids; slip agents; ultraviolet
stabilizers; viscosity depressants; and any other ingredient that
may be a desirable component of the resulting foamed polymer.
[0364] A preferred foam stabilizer may include a silicone based
foam stabilizer, such as BYK 8020 for PVC plastisol.
[0365] In some embodiments, the foamable composition does not
contain another blowing agent other than the functionalized
particulate bicarbonate.
[0366] In other embodiments, the foamable composition does not
contain any blowing agent which is exothermic. In particular
embodiments, the foamable composition does not contain a blowing
agent which liberates nitrogen gas and/or ammonia. Examples of
blowing agents which liberate nitrogen gas are exothermic blowing
agents such as azodicarbonic acid diamide (azodicarbonamide, ADC,
ADCA, CAS No. 123-77-3), the sulfonhydrazides
4,4'-oxybis(benzenesulfonylhydrazide) (OBSH, CAS No. 80-51-3) and
p-toluenesulfonylhydrazide, (TSH, CAS No. 1576-35-8).
[0367] In preferred embodiments, the foamable polymer composition
does not contain azodicarbonamide.
[0368] In alternate or additional preferred embodiments, the
foamable polymer composition does not contain
benzenesulfonylhydrazide.
[0369] In alternate or additional embodiments, the foamable polymer
composition does not contain p-toluenesulfonylhydrazide.
Process for Preparing the Foamable Composition
[0370] Another aspect of the present invention relates to a process
for preparing the foamable polymer composition as described above,
wherein the process comprises: [0371] mixing the components of the
foamable polymer composition as provided herein, wherein a
component of the foamable polymer composition is the functionalized
particulate bicarbonate.
[0372] The process for preparing the foamable polymer composition
can be carried out in conventional equipment, for example made of
Austenitic Stainless Steel (304L-316L etc). The process can also be
carried out in non-metallic materials like plastics, glass and
ceramics for chemical use.
[0373] Preferably, the mixing step in the process is carried out
under continuous mixing. Because the foamable polymer composition
has a relatively high viscosity, a powerful mixing is required for
obtaining a homogeneous foamable polymer composition. Moreover,
because the blowing effect already starts taking place during the
mixing, the speed of mixing should be sufficiently high in order to
achieve a good homogenisation within a short period of time.
Preferably, the homogenisation is achieved within less than about
20 seconds during the mixing step(s) of the process. The selection
of the mixing conditions depends upon the specific characteristics
of the equipment. The mixing step(s) of the process for preparing
the foamable polymer composition can be carried out at any suitable
temperature as in conventional foam production, the process can for
example be carried out at relatively low temperatures (ambient)
ranging between about 0.degree. C. and about 30.degree. C., for
instance at about 20-25.degree. C.
[0374] For example, a PVC plastisol composition may be prepared by
mixing [0375] the functionalized particulate bicarbonate in powder
form as described herein, [0376] at least one plasticizer, [0377]
at least one polyvinyl chloride polymer, [0378] optionally a foam
stabilizer; and [0379] optionally one or more polymer additives
such an inorganic filler.
[0380] A preferred foam stabilizer may include a silicone based
foam stabilizer, such as BYK 8020 for PVC plastisol.
[0381] The components of the PVC plastisol composition may be
dispersed on a high speed mixer and then de-aerated under
vacuum.
[0382] The PVC plastisol composition may optionally comprise a
functionalized particulate second compound used as supplemental
chemical blowing agent for foaming (as described herein). The
functionalized particulate second compound may be a functionalized
particulate carboxylic or polycarboxylic acid, derivative, or salt
thereof. The functionalized particulate second compound may be
selected from the group consisting of: fumaric acid, tartaric acid,
citric acid, salts thereof (such as sodium hydrogen citrate,
disodium citrate), esters thereof, and any combination thereof
Process for Preparing a Foamed Polymer
[0383] A further aspect of the present invention relates to a
process for preparing a foamed polymer, wherein the above described
foamable polymer composition is heated. Thus, the process for
preparing a foamed polymer can comprise the following step: [0384]
mixing the components of the foamable polymer composition as
provided herein; and [0385] heating the foamable polymer
composition obtained from mixing.
[0386] Preferably, the heating step is carried out immediately
after the completion of the mixing step.
[0387] The process for preparing a foamed polymer may include a
shaping step such as extrusion or spreading. Preferably, the
heating step is carried out immediately after the completion of the
mixing and shaping steps.
[0388] The heating step can be carried out at a temperature from
about 120.degree. C. and up to about 220.degree. C., or from about
120.degree. C. and up to about 210.degree. C., or from about
120.degree. C. and up to about 200.degree. C., depending on the
resin and the composition of plastisol.
[0389] The time of heating in the heating step depends on the
formulation of plastisol, shape of the material, temperature and
the like. In the a process for preparing a foamed polymer from the
above-mentioned foamable polymer composition, the gelation time
during the heating period in the presence of the functionalized
particulate bicarbonate as the blowing agent is less than that in
the presence of azodicarbonamide as the blowing agent (while all
other components remain the same).
[0390] When foamable polymer composition comprises the
functionalized particulate bicarbonate, the gelation time at
temperature above glass transition temperature Tg and/or above
melting temperature Tm of the polymer preferably is less than 180
seconds, such as less than 125 seconds, in particular less than 90
seconds, preferably 80 seconds or less, or 70 seconds or less, or
more preferably 60 seconds or less.
[0391] Regarding a PVC plastisol, the resulting liquid PVC paste
(plastisol) can be spread coated at a certain thickness on a
surface (for example, a paper, in particular a silicone paper) and
heated in an oven (e.g., Thermosol Werner Mathis) set at a curing
(gelation) temperature (generally between 150.degree. C. and
210.degree. C. or 200.degree. C., such as from 180.degree. C. to
210.degree. C., or from 185.degree. C. to 210.degree. C., or from
190.degree. C. to 210.degree. C., or from 200.degree. C. to
210.degree. C.) for a time of 130 seconds or less, such as for a
time of 120 seconds to 30 seconds, preferably for a time of 120
seconds to 60 seconds, more preferably for a time of 120 seconds to
90 seconds.
[0392] Generally the time at which the plastisol is held at the
gelation temperature depends on the foaming agent used. For some
foaming agents shorter gelation times can be of advantage, such as
for amino acids and in particular leucine as blowing agent where
polymer foams of good experience and expansion rate are obtained at
rather short gelation times of below 100 seconds, in particular
below 80 seconds, such as in the range of 50 to 70 seconds. For
bicarbonate particles being functionalized with an amino acid good
results at a short time are also in particular achieved if the
gelation temperature is rather low, such as below 200.degree. C.,
in particular in the range of 175 to 195.degree. C. If stearic acid
is used as additive in the functionalized particulate bicarbonate
of the present invention the same gelation times and gelation
temperatures as for amino acid additives are preferred.
[0393] For some embodiments of a process for manufacturing a PVC
polymer, when the foamable polymer composition is heated, the
temperature suitable for liberating CO2 gas from the functionalized
particulate sodium bicarbonate and melting a PVC polymer may be
from 190 to 210.degree. C., preferably from 200 to 210.degree. C.,
during a gelation time from 90 seconds to 120 seconds at a
temperature to provide a foamed PVC polymer.
[0394] When the foamable polymer composition is spread coated on a
surface before heating and polymer melting, the foamed polymer may
have an expansion ratio of at least 270, preferably at least 280,
more preferably at least 300 and/or has a density of less than 0.6
g/cm.sup.3, preferably less than 0.55 g/cm.sup.3, more preferably
at most 0.5 g/cm.sup.3. The expansion ratio is calculated based on
the ratio of a final thickness over an initial thickness of a
spread coated layer of the foamable polymer composition as that
layer gets heated in an oven.
[0395] Foamed polymeric products produced using the blowing agent
and the above discussed foamable polymer composition can be made by
processes that involve extrusion, calendering, injection molding,
coating, expansion casting or rotational molding.
Foamed Polymer
[0396] A further aspect of the present invention relates to a
foamed polymer, wherein the foamed polymer is obtainable from the
foamable composition as described above.
[0397] In one embodiment of the invention, the foamed polymer is a
flexible foamed polymer. In this embodiment, the foamed or extruded
polymer is preferably flexible polyvinyl chloride and can be
advantageously used [0398] for flooring applications; [0399] for
production of wall paper foam based; [0400] as artificial leather;
or [0401] as technical foam.
[0402] The functionalized particulate bicarbonate is preferably
used as a blowing agent for foamed or extruded polymers (such as
foamed PVC or polyurethanes; extruded PVC, polyolefins,
polyamides), preferably used as an endothermic blowing agent.
Non-limiting examples of polymers are polyvinyl chloride (PVC),
polyurethanes, polyolefins (PO, PE, PP), styrenics (PS, ABS, ASA,
SAN), engineering resins, polyphenylene oxide, polyamides,
polyimides, and natural and synthetic rubber such as nitrile
butadiene rubber (NBR) or chloroprene rubber (CR).
[0403] When the foamable polymer composition is spread coated on a
surface before heating and polymer melting, the foamed polymer may
have an expansion ratio of at least 270, preferably at least 280,
more preferably at least 300. The expansion ratio is calculated
based on the ratio of a final thickness over an initial thickness
of a spread coated layer of the foamable polymer composition as
that layer gets heated in an oven. The expansion ratio may be from
270 up to 450, or from 280 up to 445, or from 290 up to 440, or
from 300 up to 440.
[0404] In some embodiments, the foamed polymer is a PVC foam with a
density of less than 0.65 g/cm.sup.3 or of less than 0.6
g/cm.sup.3, preferably less than 0.58 g/cm.sup.3, more preferably
at most 0.55 g/cm.sup.3, most preferably at most 0.5 g/cm.sup.3 or
at most 0.45 g/cm.sup.3. In some embodiments in which a PVC foam is
made from a foamable PVC composition containing a functionalized
particulate bicarbonate with at least one additive, the PVC foam
has a density from 0.3 to 0.65 g/cm.sup.3, preferably a density
from 0.33 to 0.58 g/cm.sup.3, more preferably a density from 0.33
to 0.5 g/cm.sup.3 or even a density from 0.33 to 0.45 g/cm.sup.3.
The additive is preferably selected from the group consisting of
beeswax, carnauba wax, glycerol mono stearate, poly(meth)acrylate,
epoxidized soybean oil, arabic gum, linoleic acid, maltodextrin,
polyvinyl alcohol, lauric acid, rosin acid, starch, stearic acid, a
polyoxyethylene compound (like BIK3155, polyethylene glycol e.g.,
PGE400, PEG4000), leucine, and any combination of two or more
thereof.
[0405] The present invention is based on the discovery of the
effects of the additive mentioned in the present specification, for
which the different variants of the method and/or of the product
obtained by said variants of the method are described in more
detail below.
ITEM 1. A chemical blowing agent for foaming a thermoplastic
polymer precursor, for example PVC plastisol or a polymer resin in
an extrusion process,
[0406] said chemical blowing agent comprising a functionalized
particulate bicarbonate,
[0407] wherein said functionalized particulate bicarbonate contains
at least one additive,
[0408] wherein the chemical blowing agent does not contain a
compound which liberates nitrogen gas during heating; and
[0409] wherein said additive in the functionalized particulate
bicarbonate is at least one following compound: [0410] one or more
polymers; [0411] one or more amino acids, any derivative thereof,
and salts thereof; [0412] one or more inorganic salts; [0413] one
or more oils; [0414] one or more fats; [0415] one or more resin
acids, any derivative thereof, and salts thereof; [0416] one or
more fatty acids, any derivative thereof, and salts thereof; [0417]
a carboxylic or polycarboxylic acid, derivative thereof (such as
esters), or salts thereof; [0418] one or more soaps; [0419] one or
more waxes; or [0420] any combinations thereof. ITEM 2. The
chemical blowing agent according to ITEM 1, wherein the additive in
the functionalized particulate bicarbonate is at least one compound
selected from the group consisting of an amino acid, derivative
thereof, or salt thereof, preferably at least one compound selected
from the group consisting of casein, gelatin, glycine, proline,
hydroxyproline, glutamic acid, alanine, arginine, aspartic acid,
lysine, pectin, serine, leucine, valine, phenylalanine, threonine,
isoleucine, hydroxylysine, methionine, histidine, tyrosine and
combinations thereof, more preferably leucine. ITEM 3. The chemical
blowing agent according to ITEM 1, wherein the additive in the
functionalized particulate bicarbonate is at least one compound
selected from the group consisting of a fatty acid, derivative
thereof (such as ester), or salt thereof. ITEM 4. The chemical
blowing agent according to any of ITEMS 1 to 3, wherein the
functionalized particulate bicarbonate comprises sodium
bicarbonate. ITEM 5. The chemical blowing agent according to any of
ITEMS to 4, wherein the functionalized particulate bicarbonate
comprises at least 50% by weight and less than 100% by weight of
the bicarbonate component, and from 50% or less to 0.02% by weight
of said additive. ITEM 6. The chemical blowing agent according to
any of ITEMS 1 to 5, wherein the functionalized particulate
bicarbonate comprises at least 90% by weight and less than 100% by
weight of the bicarbonate component, and from 10% or less to 0.02%
by weight of said additive. ITEM 7. The chemical blowing agent
according to any of ITEMS 1 to 6, wherein the particles of the
functionalized particulate bicarbonate have a particle size
distribution of D.sub.50 of more than 1 .mu.m and at most 25 .mu.m.
ITEM 8. The chemical blowing agent according to any of ITEMS 1 to
6, wherein the particles of the functionalized particulate
bicarbonate have a particle size distribution of D.sub.50 of at
most 1 .mu.m. ITEM 9. The chemical blowing agent according to any
of ITEMS 1 to 8, wherein the functionalized particulate bicarbonate
obtained by at least one of the following processes: [0421] by
spray-drying (also known as atomization), wherein the additive is
dissolved in the bicarbonate-containing solution. [0422] by
grinding or co-grinding (also known as milling or co-milling) with
the additive(s) in emulsion or powder form; [0423] by spray coating
and granulation within a fluidized bed, [0424] by spray
agglomeration within a fluidized bed, [0425] by spray chilling
(e.g., spray cooling, spray freezing), [0426] by roller compaction,
and/or [0427] by extrusion, including simultaneous
mixing/extrusion. ITEM 10. The chemical blowing agent according to
any of ITEMS 1 to 9, further comprising an second compound which
liberates CO2 upon heating, said second compound being selected
from the group consisting of a carboxylic or polycarboxylic acid,
derivative thereof (such as esters), or salts thereof. ITEM 11. The
chemical blowing agent according to ITEM 10, wherein said second
compound is functionalized with at least one additive which is
different or the same as the one in the functionalized particulate
bicarbonate. ITEM 12. The chemical blowing agent according to ITEM
10 or 11, wherein said second compound is at least one of: [0428]
fumaric acid, [0429] tartaric acid, [0430] citric acid, citrates
(such as sodium hydrogen citrate, disodium citrate), or esters of
citric acid; or combination thereof. ITEM 13. A foamable polymer
composition, comprising a polymer, optionally a foaming stabilizer,
and the chemical blowing agent according to ITEMS 1 to 12. ITEM 14.
The foamable polymer composition according to ITEM 13, wherein the
polymer is a PVC, a polyurethane, a polyolefin, or a polyamide.
ITEM 15. A foamable PVC plastisol composition, comprising a PVC
resin, optionally a foaming stabilizer, and the chemical blowing
agent according to ITEMS 1 to 12. ITEM 16. The foamable PVC
plastisol composition according to ITEM 15, which does not contain
azodicarbonamide, benzenesulfonylhydrazide, and/or
p-toluenesulfonylhydrazide. ITEM 17. A process for manufacturing a
polymer, comprising heating the foamable polymer composition
according to ITEMS 13 or 14 which comprises the functionalized
particulate bicarbonate at a temperature suitable for liberating
CO2 gas and melting the polymer during a gelation time at a
temperature above glass transition temperature Tg and/or above
melting temperature Tm of the polymer which is less than 90
seconds. ITEM 18. A polymer obtained by the process of ITEM 17,
wherein the polymer is a PVC, a polyurethane, a polyolefin, or a
polyamide. ITEM 19. A process for manufacturing a polymer,
comprising heating the foamable PVC plastisol composition according
to ITEMS 15 or 16 which comprises the functionalized particulate
bicarbonate at a temperature suitable for liberating CO2 gas and
melting the PVC resin during a gelation time, wherein said gelation
time with the chemical blowing agent comprising the functionalized
particulate is less than the gelation time that would be obtained
with a chemical blowing agent liberating N2, all other components
in the foamable PVC plastisol composition being the same. ITEM 20.
A foamed PVC obtained by the process of ITEM 19. ITEM 21. A
chemical blowing agent for foaming a thermoplastic polymer
precursor, for example PVC plastisol or a polymer resin in an
extrusion process,
[0431] said chemical blowing agent comprising a functionalized
particulate bicarbonate,
[0432] wherein said functionalized particulate bicarbonate contains
at least one additive, and
[0433] wherein said additive in the functionalized particulate
bicarbonate is at least one following compound: [0434] one or more
polymers; [0435] one or more amino acids, any derivative thereof,
and salts thereof; [0436] one or more inorganic salts; [0437] one
or more oils; [0438] one or more fats; [0439] one or more resin
acids, any derivative thereof, and salts thereof; [0440] one or
more fatty acids, any derivative thereof, and salts thereof; [0441]
a carboxylic or polycarboxylic acid, derivative thereof (such as
esters), or salts thereof; [0442] one or more soaps; [0443] one or
more waxes; or [0444] any combinations thereof. ITEM 22. The
chemical blowing agent according to ITEM 21, wherein the blowing
agent does not contain any further blowing agent which is an
exothermic blowing agent. ITEM 23. The chemical blowing agent
according to ITEM 21 or 22, wherein the chemical blowing agent does
not contain a compound which liberates nitrogen gas during heating.
ITEM 24. The chemical blowing agent according to any of ITEMS 21 to
23, wherein the chemical blowing agent does not contain a compound
which liberates ammonia gas during heating. ITEM 25. The chemical
blowing agent according to any of ITEMS 21 to 24, wherein the
additive in the functionalized particulate bicarbonate is at least
one compound selected from the group consisting of an amino acid,
derivative thereof, or salt thereof, preferably at least one
compound selected from the group consisting of casein, gelatin,
glycine, proline, hydroxyproline, glutamic acid, alanine, arginine,
aspartic acid, lysine, pectin, serine, leucine, valine,
phenylalanine, threonine, isoleucine, hydroxylysine, methionine,
histidine, tyrosine and combinations thereof, more preferably
leucine. ITEM 26. The chemical blowing agent according to any of
ITEMS 21 to 24, wherein the additive in the functionalized
particulate bicarbonate is at least one compound selected from the
group consisting of a fatty acid, derivative thereof (such as
ester), or salt thereof, preferably at least one compound selected
from the group consisting of lauric acid, stearic acid, glycerol
mono stearate and combinations thereof, more preferably lauric
acid. ITEM 27. The chemical blowing agent according to any of ITEMS
21 to 24, wherein the additive in the functionalized particulate
bicarbonate is at least one polymer selected from the group
consisting of polyoxyalkylenes and derivatives thereof including
polyethylene glycols, poly(meth)acrylates and derivatives thereof,
polyvinylalcohol, polysaccharides and combinations thereof,
preferably polymer selected from the group consisting of
polyvinylalcohol and polyoxyalkylenes and derivatives thereof
including polyethylene glycols. ITEM 28. The chemical blowing agent
according to ITEM 27, wherein the polysaccharides are selected from
the group consisting of modified, in particular hydrolyzed starch,
maltodextrin, arabic gum and combinations thereof, more preferably
maltodextrin. ITEM 29. The chemical blowing agent according to any
of ITEMS 21 to 24, wherein the additive in the functionalized
particulate bicarbonate is at least one resin acid, any derivative
thereof, and salts thereof, more preferably rosin acid. ITEM 30.
The chemical blowing agent according to any of ITEMS 21 to 24,
wherein the additive in the functionalized particulate bicarbonate
is at least one oil, preferably a vegetable oil or any derivative
thereof, more preferably epoxidized soy bean oil. ITEM 31. The
chemical blowing agent according to any of ITEMS 21 to 24, wherein
the additive in the functionalized particulate bicarbonate is at
least one wax selected from the group consisting of beeswax,
carnauba wax and combinations thereof. ITEM 32. The chemical
blowing agent according to any of ITEMS 21 to 31, wherein the
functionalized particulate bicarbonate comprises sodium
bicarbonate. ITEM 33. The chemical blowing agent according to any
of ITEMS 21 to 32, wherein the functionalized particulate
bicarbonate comprises at least 50% by weight and less than 100% by
weight of the bicarbonate component, and from 50% or less to 0.02%
by weight of at least one of said additive. ITEM 34. The chemical
blowing agent according to any of ITEMS 21 to 33, wherein the
functionalized particulate bicarbonate comprises at least 65% by
weight and less than 100% by weight of the bicarbonate component,
and from 35% or less to 0.02% by weight of at least one of said
additive. ITEM 35. The chemical blowing agent according to any of
ITEMS 21 to 34, wherein the particles of the functionalized
particulate bicarbonate have a particle size distribution of
D.sub.50 of more than 1 .mu.m and at most 250 .mu.m, preferably at
most 100 .mu.m, more preferably at most 60 .mu.m, yet more
preferably at most 40 .mu.m, yet most preferably at most 25 .mu.m.
ITEM 36. The chemical blowing agent according to any of ITEMS 21 to
34, wherein the particles of the functionalized particulate
bicarbonate have a particle size distribution of D.sub.50 of at
most 1 .mu.m. ITEM 37. The chemical blowing agent according to any
of ITEMS 21 to 36, wherein the functionalized particulate
bicarbonate is obtained by at least one of the following processes:
[0445] by spray-drying (also known as atomization), wherein the
additive is dissolved in the bicarbonate-containing solution.
[0446] by grinding or co-grinding (also known as milling or
co-milling) with the additive(s) in emulsion or powder form; [0447]
by spray coating and granulation within a fluidized bed, [0448] by
spray agglomeration within a fluidized bed, [0449] by spray
chilling (e.g., spray cooling, spray freezing), [0450] by roller
compaction, and/or [0451] by extrusion, including simultaneous
mixing/extrusion. ITEM 38. The chemical blowing agent according to
ITEM 37, wherein the functionalized particulate bicarbonate is
obtained by at least one said process and is further subjected to
milling to reduce its mean particle size. ITEM 39. The chemical
blowing agent according to any of ITEMS 21 to 38, further
comprising an second compound which liberates CO2 upon heating,
said second compound being selected from the group consisting of a
carboxylic or polycarboxylic acid, derivative thereof (such as
esters), or salts thereof. ITEM 40. The chemical blowing agent
according to ITEM 39, wherein said second compound is
functionalized with at least one additive which is different or the
same as the one in the functionalized particulate bicarbonate,
preferably the same additive. ITEM 41. The chemical blowing agent
according to ITEM 39 or 40, wherein said second compound is at
least one of: [0452] fumaric acid, [0453] tartaric acid, [0454]
citric acid, citrates (such as sodium hydrogen citrate, disodium
citrate), or esters of citric acid; or combination thereof. ITEM
42. A foamable polymer composition, comprising a polymer,
optionally a foaming stabilizer, and the chemical blowing agent
according to any of ITEMS 21 to 41. ITEM 43. The foamable polymer
composition according to ITEM 42, wherein the polymer is a PVC, a
polyurethane, a polyolefin, or a polyamide. ITEM 44. A foamable PVC
plastisol composition, comprising a PVC resin, optionally a foaming
stabilizer, and the chemical blowing agent according to any of
ITEMS 21 to 41. ITEM 45. The foamable PVC plastisol composition
according to ITEM 44, which does not contain azodicarbonamide,
benzenesulfonylhydrazide, and/or p-toluenesulfonylhydrazide. ITEM
46. A process for manufacturing a polymer, comprising heating the
foamable polymer composition according to ITEMS 42 or 43 which
comprises the functionalized particulate bicarbonate at a
temperature suitable for liberating CO2 gas and melting the polymer
during a gelation time at a temperature above glass transition
temperature Tg and/or above melting temperature Tm of the polymer
which is less than 130 seconds. ITEM 47. A foamed polymer obtained
by the process of ITEM 46, wherein the polymer is a PVC, a
polyurethane, a polyolefin, or a polyamide. ITEM 48. A process for
manufacturing a PVC polymer, comprising heating the foamable PVC
polymer composition according to ITEMS 44 or 45 which comprises the
functionalized particulate bicarbonate and the PVC resin at a
temperature suitable for liberating CO2 gas and melting the PVC
polymer during a gelation time from 90 seconds to 120 seconds at a
temperature from 190 to 210.degree. C., preferably from 200 to
210.degree. C., to provide a foamed PVC polymer. ITEM 49. The
process according to ITEM 48, wherein the foamable polymer
composition is spread coated on a surface before heating and
melting, and wherein the foamed polymer has an expansion ratio of
at least 270, preferably at least 280, more preferably at least 300
and/or has a density of less than 0.6 g/cm.sup.3, preferably less
than 0.55 g/cm.sup.3, more preferably at most 0.5 g/cm.sup.3. ITEM
50. A process for manufacturing a polymer, comprising heating the
foamable PVC plastisol composition according to ITEMS 44 or 45
which comprises the functionalized particulate bicarbonate at a
temperature suitable for liberating CO2 gas and melting the PVC
resin during a gelation time, wherein said gelation time with the
chemical blowing agent comprising the functionalized particulate is
less than the gelation time that would be obtained with a chemical
blowing agent liberating N2, all other components in the foamable
PVC plastisol composition being the same. ITEM 51. A foamed PVC
obtained by the process of any of ITEMS 48, 49 or 50.
[0455] The following examples are given by way of non-limiting
illustration of the present invention, and variations thereof that
are readily accessible to a person skilled in the art.
EXAMPLES
Co-Milling
[0456] Milling was performed continuously in an UltraRotor III
instrument from Jacketing, equipped with a classifier. Sodium
Bicarbonate particles were loaded at the bottom of the mill from 10
to 300 kg/h under air injection at room temperature. The
functionalization additive was added at the mid level of the mill
in order to reach the desired weight content of functionalization
additive in the mix. Mill rotary speed and classifier rotary speed
were selected to reach the desired particle size distribution.
Extrusion-Mixing
[0457] The extrusion-mixing process was performed continuously in a
UCP25 instrument from HASLER Group which had an inlet point and
paddles. Sodium Bicarbonate particles were loaded at the UCP25
inlet point from 1 to 2 kg/h. The functionalization additive was
loaded a few centimeters after the main inlet point, from 0.1 to 1
kg/h. Rotary speed of the paddles was 50 rpm. Instrument
temperature was kept at room temperature.
[0458] Milling after Extrusion-Mixing
[0459] The functionalized sodium bicarbonate product exiting the
extrusion-mixing process was continuously injected at the top of a
UPZ100 mill from Hosokawa Alpine at a loading rate of from 0.5 to
10 kg/h. The mill has a rotor speed selected between 10,000 and
17,000 rpm and the mill was operated at room temperature.
Agglomeration (=>FB Agglomeration+Milling)
[0460] Product out of fluid bed agglomeration process was injected
at the top of a UPZ100 mill from Hosokawa Alpine. Formulated sodium
Bicarbonate was loaded from 0.5 to 10 kg/h and the mill rotor speed
was selected between 10.000 and 17.000 rpm. Process temperature was
the room temperature.
Fluid Bed Spray Coating (=>FB Coating+Milling)
[0461] Spray coating was performed in a batch fluidized bed
WFP-mini instrument from DMR Prozesstechnologie which comprised a
fluidization chamber, means to load particles, means to inject the
functionalization additive generally in liquid form, and means to
inject a fluidization gas at the bottom of that chamber. Sodium
Bicarbonate particles were initially loaded from 100 g to 1 kg in
the fluidization chamber. Fluidization air was heated from 10 to
100.degree. C., and its flowrate was between 10 and 40 m.sup.3/h. A
liquid containing the functionalization additive was sprayed from
the chamber bottom at a temperature between 20 and 90.degree. C.
The liquid was generally a solution of the functionalization
additive in a solvent, preferably an aqueous solution with a
concentration between 1 and 80 wt %. The liquid was sprayed under a
flowrate of up to 20 g/min in order to evaporate the solvent (e.g.,
water) and coat the functionalization additive (generally by way of
crystallization) onto the sodium bicarbonate particles. The content
of the coated functionalization additive was between 1 and 70 wt
%.
[0462] The product obtained after spray coating was generally
milled. The spray coated particles that exited the fluid bed
coating process were injected at the top of a UPZ100 mill from
Hosokawa Alpine at a loading rate of from 0.5 to 10 kg/h and the
mill had a rotor speed selected between 10,000 and 17,000 rpm and
was operated at room temperature.
Preparation of PVC plastisol A method for making a PVC plastisol
may generally follow the following steps: [0463] the weight of the
PVC resin is measured in a 2-liter stainless steel pot and the rest
of the formula is weighed apart; [0464] The stainless steel pot is
placed under a hydraulic mixer (Pendraulik) with a deflocculating
shear blade (rotor blade diameter 70 mm) [0465] Stirring at 250
rev/min during addition of the mineral filler, plasticizer and
blowing agent [0466] Stirring at 4200 rev/min for 45 seconds, once
the powders are suspended (temperature about 40-50.degree. C., if
time higher agitation, T may rise to 60-70.degree. C.) [0467]
Vacuum preparation to strip air bubbles. When the level of
preparation goes up into the beaker, the beaker may be tapped on
the bench to remove bubbles faster. [0468] When the level of
preparation is stable in the presence of the vacuum, count 5
minutes before cutting vacuum and then end air stripping. [0469] To
avoid foaming, optionally adding a foam stabilizer (such as from
BYK provider) [0470] temperature setting in a Werner Mathis oven at
a preset temperature, usually T=190, 200 or 210.degree. C. [0471] A
paper (silicone paper in examples 1-12 and regular paper (from
Claire Fontaine) in examples 13-51) is installed and heated for 10
seconds to remove residual water from the paper [0472] Plastisol
mixture is spread on the paper in a thickness of 750 microns [0473]
The PVC plastisol is heated up to 2 minutes for gelation (usually
60s, 90s, 120s), [0474] Wait until the plastisol is cooled for
remove it from the paper. Thw following chemicals were used in the
examples:
TABLE-US-00001 [0474] SolVin .RTM. 367 NF PVC resin of Inovyn
SolVin .RTM. 266 SC PVC resin of Inovyn Durcal .RTM. 15 CaCO.sub.3
of Omya Palatinol .RTM. (DINP) di-isononyl of BASF phthalate
(C.sub.26H.sub.42O.sub.4) Disperplast 1150 of BYK Viscobyk .RTM.
4040 of BYK BYK 3155 of BYK BYK 8070 of BYK Genitron .RTM. SCE (70%
azodicarbonamide + of Lanxess 30% kicker) MB10 feet fusing mono
ester of of ExxonMobil benzoic acid and isodecyl alcohol Beeswax of
Dousselin Carnauba wax of Dousselin Bergabest GS SE Glycerol mono
stearate of Berg & Schmidt (GMS) Eudragit .RTM. RL 30D
poly(meth)acrylate of Evonik HSE Drapex .RTM. 39 epoxidized soy
bean oil by Galata Chemicals and 392 PEG400 of Sigma Aldrich
PFG4000 of INEOS Oxide Poval .RTM. Polyvinylalcohol of Kuvary
Palmac .RTM. 99-12 lauric acid of Berg & Schmidt Rosin acid of
Moulage Form Composite HiCap .RTM. 100 starch of Ingredion Stearic
acid of FACI
Example 1 (not in Accordance with Invention)
Examples 2-4
Additive=Leucine (in Accordance with Invention)
[0475] A functionalized sodium bicarbonate was prepared by
spray-drying sodium bicarbonate with 1000 ppm leucine (as an amino
acid additive).
[0476] For Examples 2-4, PVC Plastisol compositions were prepared
by using the functionalized sodium bicarbonate in powder form as
the blowing agent. The functionalized sodium bicarbonate in powder
form was mixed in the presence at least one plasticizer, at least
one polyvinyl chloride polymer, and optionally one or more polymer
additives such an inorganic filler.
[0477] The PVC Plastisol composition of Example 1 was prepared by
using azodicarbonamide as the blowing agent. The other components
of the plastisol of Example 1 were the same as those used in
Examples 2-4.
[0478] The specific components and amounts as mentioned in Table 1
were chosen.
[0479] In each example, the components were dispersed on a high
speed mixer and them mixed and de-aerated under vacuum.
[0480] The resulting liquid PVC pastes (plastisols) of Examples 1
to 4 were in each case spread coated at a thickness of about 0.75
mm on silicone paper and heated in a Thermosol Werner Mathis oven
set at 185.degree. C. for 120 seconds for Example 1 (control) or
from 60, 80, 120 seconds for Examples 2 to 4 (invention),
respectively.
[0481] The surface and structure of the foam was assessed visually.
The expansion rate was the ratio of the difference between the
final thickness of the foamed product after Werner Mathis oven
heating and the initial thickness of the spread coated layer (here
about 0.75 mm) before it passed the Werner Mathis oven heating,
over the initial thickness. The expansion ratio was calculated as
the ratio of the final thickness of the foamed product over the
initial thickness of the spread coated layer (here about 0.75 mm).
The results are provided in TABLE 1, where "PCR" means parts by
weight of PVC resin.
TABLE-US-00002 TABLE 1 Examples 1 2 3 4 PLASTISOL Spray-dried Bicar
+ Spray-dried Bicar + Spray-dried Bicar + BASE AZO 1000 ppm leucine
1000 ppm leucine 1000 ppm leucine PCR PCR PCR PCR PVC resin SolVin
367 NF 89.9 89.9 89.9 89.9 SolVin 266 SC 10.1 10.1 10.1 10.1
Inorganic filler Durcal 15 (CaCO.sub.3) 80.1 80.1 80.1 80.1
Plastisizer Foam stabilizer 58.1 24.2 24.2 24.2 (DINP) Wetting and
Disperplast 1150 0.3 0.3 0.3 0.3 dispersing agent of TiO.sub.2 and
ZnO Viscosity Modifiers Viscobyk 4040 3.2 3.2 3.2 3.2 Prevent the
foam BYK 3155 0.3 0.3 0.3 0.3 release agent Foam stabilizer BYK
8070 -- 3.0 3.0 3.0 TiO2 2.3 2.3 2.3 2.3 Blowing agent
Azodicarbonamide 2.2 -- -- -- Blowing agent Sodium
bicarbonate.sup.(1) -- 6.6 6.6 6.6 ZnO 1 Conditions/Results
Pre-gelification phase 30 sec at 90.degree. C. 30 sec at 90.degree.
C. 30 sec at 90.degree. C. 30 sec at 90.degree. C. Gelification
phase 2 min at 185.degree. C. 60 sec at 185.degree. C. 80 sec at
185.degree. C. 120 sec at 185.degree. C. Coating appearance Very
smooth Smooth Slightly granular Slightly granular Thickness (in mm)
2.4 2.18 1.43 1.05 Expansion rate (%) 220 191 91 40 Expansion ratio
(%) 320 290 190 140 .sup.(1)Spray-dried sodium bicarbonate, 1000
ppm Leucine d.sub.10 = 5 .mu.m d.sub.50 = 19 .mu.m d.sub.90 = 34
.mu.m
Examples 5-8 (not in Accordance with Invention)
[0482] For Examples 6-8, PVC Plastisol compositions were prepared
by using a non-functionalized sodium bicarbonate in powder form as
the blowing agent. The non-functionalized sodium bicarbonate in
powder form was mixed in the presence at least one plasticizer, at
least one polyvinyl chloride polymer, and optionally one or more
polymer additives such an inorganic filler. A PVC Plastisol
composition of Example 5 was prepared by using azodicarbonamide as
the blowing agent. The other components of the plastisol of Example
5 were the same as those used in Examples 6-8. The specific
components and amounts as mentioned in TABLE 2 were chosen. "PCR"
in TABLE 2 means parts by weight of resin. In each example 5-8, the
components were dispersed on a high speed mixer and them mixed and
de-aerated under vacuum.
[0483] The resulting liquid PVC pastes (plastisols) of Examples 5-8
were in each case spread coated at a thickness of about 0.75 mm on
silicone paper and heated in a Thermosol Werner Mathis oven set
with a gelation period at 185.degree. C. for 120 seconds.
[0484] Examples 6 to 8 with non-functionalized bicarbonates as
foaming agent gave poor expansion results compared to the Example 5
using azodicarbonamide as the blowing agent. After gelling, PVC
plastisols surfaces of Examples 6 to 8 had a very granular
appearance which was a sign of surface coalescence of gas bubbles
in the polymer melt.
TABLE-US-00003 TABLE 2 Examples 5 8 A 6 7 D PLASTISOL B C Bicar
BASE AZO Bicar 0/6P Bica 0/50 0/50 PCR PCR PCR PCR PVC resin PVC
resin 100 100 100 100 Inorganic CaCO.sub.3 40 40 40 40 filler
Plasticizer Palatinol N 65 65 65 65 (DINP) MB10 20 Blowing
Azodicarbonamide + 4.5 1.1 1.1 1.1 Agent Kicker.sup.(d) Bicar 0/50
crushed.sup.(1) X 8 8 Bicar 0/6P.sup.(2) X 6 Result Coating Very
smooth Very granular Very Very appearance granular granular
.sup.(1)Bicar 06/P trade product of Solvay .sup.(2)Bicar 0/50
crushed in Alpine 01 - d.sub.10 = 3.4 .mu.m d.sub.50 = 17.8 .mu.m
d.sub.90 = 39.6 .mu.m
Example 9 (not in Accordance with Invention)
Examples 10-12 (in Accordance with Invention)
Functionalization Additive=Stearic Acid
[0485] A functionalized sodium bicarbonate was prepared by
co-grinding sodium bicarbonate with 2 wt % stearic acid (as a fatty
acid additive).
[0486] For Examples 10-12, PVC Plastisol compositions were prepared
by using the functionalized sodium bicarbonate in powder form as
the blowing agent. The functionalized sodium bicarbonate in powder
form was mixed in the presence at least one plasticizer, at least
one polyvinyl chloride polymer, and optionally one or more polymer
additives such an inorganic filler. The PVC Plastisol composition
of Example 9 was prepared by using azodicarbonamide as the blowing
agent. The other components of the plastisol of Example 9 were the
same as those used in Examples 10-12. The specific components and
amounts as mentioned in Table 3 are chosen.
[0487] In each example, the components were dispersed on a high
speed mixer and them mixed and de-aerated under vacuum.
[0488] The resulting liquid PVC pastes (plastisols) of Examples 9
to 12 were in each case spread coated at a thickness of about 0.75
mm on silicone paper and heated in a Thermosol Werner Mathis oven
set at 185.degree. C. for 120 seconds for Example 9 (control) or
from 60, 80, 120 seconds for Examples 10 to 12 (invention),
respectively. The surface and structure of the foam was assessed
visually. The expansion rate was the ratio of the difference
between the final thickness of the foamed product after Werner
Mathis oven heating and the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating, over the initial thickness. The expansion ratio was
calculated as the ratio of the final thickness of the foamed
product over the initial thickness of the spread coated layer (here
about 0.75 mm). The results are provided in TABLE 3, where "pcr"
means parts by weight of PVC resin.
TABLE-US-00004 TABLE 3 Examples 9 10 11 12 Test 1 A B C TEST
PLASTISOL Cogrinding Cogrinding Cogrinding BASE Bicar + Bicar +
Bicar + AZO 2% 2% 2% stearic stearic stearic acid acid acid PCR PCR
PCR PCR PVC resin SolVin 367 NF 89.9 89.9 89.9 89.9 SolVin 266 SC
10.1 10.1 10.1 10.1 Inorganic filler Durcal 15 80.1 80.1 80.1 80.1
(CaCO.sub.3) Plastisizer Foam stabilizer 58.1 24.2 24.2 24.2 (DINP)
Wetting and Disperplast 0.3 0.3 0.3 0.3 dispersing agent of 1150
TiO.sub.2 and ZnO Viscosity Modifiers Viscobyk 4040 3.2 3.2 3.2 3.2
Prevent the foam BYK 3155 0.3 0.3 0.3 0.3 release agent Foam
stabilizer BYK 8070 -- 3.0 3.0 3.0 TiO2 2.3 2.3 2.3 2.3 Blowing
agent Azodicarbonamide 2.2 -- -- -- Blowing agent Sodium -- 6.6 6.6
6.6 bicarbonate.sup.(1) ZnO 1 -- -- -- Conditions/Results
Pre-gelification 30 sec at 30 sec at 30 sec at 30 sec at phase
90.degree. C. 90.degree. C. 90.degree. C. 90.degree. C.
Gelification 2 min at 60 sec at 80 sec at 120 sec at phase
185.degree. C. 185.degree. C. 185.degree. C. 185.degree. C. Coating
Very Smooth Slightly Granular appearance smooth granular Thickness
(in 2.4 2.05 1.31 0.92 mm) Expansion rate 220 185 84 36 (%)
Expansion ratio 320 270 175 120 (%) .sup.(1)Cogrinding Bicar + 2%
stearic acid coating: d.sub.10 = 2.8 .mu.m d.sub.50 = 17.1 .mu.m
d.sub.90 = 50.3 .mu.m
[0489] When tested at lower gelation times (1 min at 190.degree.
C.), the results obtained in the presence of sodium bicarbonate are
comparable to those obtained with formulation with azodicarbonamide
in terms: [0490] of obtained visual appearance of the coating
surface and [0491] of the polymer expansion rate.
[0492] The tests carried out to gelation times higher than 1 min
(80 sec and 120 sec) show surfaces having a granular surface
appearance from the plastisols based on functionalized bicarbonate,
meaning that gas bubble coalescence occurs in the cellular
structure.
Example 13 (not in Accordance with Invention)
Blowing Agent=Azodicarbonamide
[0493] The PVC Plastisol compositions of Example 13 were prepared
in a Dispermat apparatus by using azodicarbonamide as the blowing
agent. The azodicarbonamide product used was Genitron SCE (Lanxess)
which consisted of 75 wt % azodicarbonamide and 25 wt % kicker
(zinc oxide/zinc stearate). The components of the plastisol were
dispersed on a high speed mixer and then mixed and de-aerated under
vacuum. The resulting liquid PVC pastes (plastisols) of Example 13
are in each case spread coated at a thickness of about 0.75 mm on a
piece of paper (Claire Fontaine) and heated in a Thermosol Werner
Mathis oven set at 200 or 210.degree. C. for 90 or 120 seconds.
[0494] The expansion rate was the ratio of the difference between
the final thickness of the foamed product after Werner Mathis oven
heating and the initial thickness of the spread coated layer (here
about 0.75 mm) before it passed the Werner Mathis oven heating,
over the initial thickness. The expansion ratio was calculated as
the ratio of the final thickness of the foamed product over the
initial thickness of the spread coated layer (here about 0.75 mm).
The specific components and amounts in each plastisol, the oven
temperature, the time for gelation, the thickness of the foamed
product after oven heating, the expansion rate, the expansion
ratio, and the density of the PVC foams are provided in TABLE 4
where "pcr" means parts by weight of PVC resin.
TABLE-US-00005 TABLE 4 Azodicarbonamide as blowing agent Example 13
Type of agent blowing Azodicarbonamide Plastisol Ex. 13 p1 13 p2 13
p3 13 p4 13 p5 13 p6 PVC resin 367 NF 100 100 100 100 100 100
Filler CaCO.sub.3 120 120 120 120 120 120 Plastisizer Palatinol N
80 80 80 80 80 80 Defoamer BYK3155 -- 3 -- 3 -- 3 Blowing Genitron
SCE 4 4 4 4 4 4 agent (incl .25% zinc oxide/stearate) Gelation temp
(.degree. C.) 200 200 210 210 210 210 Gelation Time (sec.) 120 120
120 120 90 90 Thickness (mm) 3.16 3.06 3.33 3.42 2.58 2.80
Expansion rate (%) 320 310 340 360 240 270 Expansion ratio (%) 420
410 440 460 340 370 Density (g/cm.sup.3) 0.37 0.36 0.32 0.34 0.43
0.39
Example 14 (in Accordance with Invention)
With Functionalization Additive=Beeswax
[0495] One sample of functionalized sodium bicarbonate was prepared
by spray coating sodium bicarbonate particles in a fluidized bed
with beeswax and then milling. The functionalized sodium
bicarbonate sample is identified as Example 14A (20 wt %
beeswax).
[0496] For Example 14, PVC Plastisol compositions were prepared in
a Dispermat apparatus. In each example, the components of the
plastisols were dispersed on a high speed mixer and then mixed and
de-aerated under vacuum. The resulting liquid PVC pastes
(plastisols) of Example 14 are in each case spread coated at a
thickness of about 0.75 mm on a piece of paper (Claire Fontaine)
and heated in a Thermosol Werner Mathis oven set at 200 or
210.degree. C. for 90 or 120 seconds. The expansion ratio is
calculated as the ratio of the thickness of the foamed product
after Werner Mathis oven heating over the initial thickness of the
spread coated layer (here about 0.75 mm) before it passed the
Werner Mathis oven heating. The specific components and amounts in
each plastisol, the oven temperature, the time for gelation, the
thickness of the foamed product after oven heating, the expansion
ratio, and the density of the PVC foams are provided in TABLE 5,
where "pcr" means parts by weight of PVC resin.
TABLE-US-00006 TABLE 5 Functionalization Additive = Beeswax Example
14 Functionalized Ex. 14A Bicarbonate as blowing agent Funct.
Method Spray Coating with fluidized bed/milling Funct. Additive 20
wt % Beeswax D10/D50/D90 4.4/21/65 (.mu.m) Plastisol Ex. 14 p1 14
p2 14 p3 14p4 PVC resin 367 NF (pcr) 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 Plastisizer Palatinol N (pcr) 80
80 80 80 Defoamer BYK3155 (pcr) 3 3 3 3 Blowing Func. Bicar. (pcr)
8 8 8 8 agent Gelation temp (.degree. C.) 200 200 210 210 Gelation
Time (sec.) 90 120 90 120 Thickness (mm) 2.11 2.12 2.66 2.10
Expansion ratio (%) 280 280 350 280 Density (g/cm.sup.3) 0.53 0.51
0.42 0.51
Example 15 (in Accordance with Invention)
Functionalization Additive=Carnauba Wax
[0497] One sample of functionalized sodium bicarbonate was prepared
by extrusion of sodium bicarbonate particles with carnauba wax, and
then milling. The functionalized sodium bicarbonate sample is
identified as Example 15A (10 wt % carnauba wax).
[0498] For Example 15, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio calculated as the
ratio of the thickness of the foamed product after Werner Mathis
oven heating over the initial thickness of the spread coated layer
(here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 6, where "pcr" means
parts by weight of PVC resin.
TABLE-US-00007 TABLE 6 Functionalization Additive = Carnauba wax
Example 15 Functionalized Ex. 15A Bicarbonate Funct. Method
Extrusion/milling Funct. Additive 10 wt % carnauba wax D10/D50/D90
(.mu.m) 10/57/125 Plastisol Ex. 15 p1 15 p2 15 p3 PVC resin 367 NF
(pcr) 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 Plastisizer
Palatinol N (pcr) 80 80 80 Defoamer BYK3155 (pcr) 3 3 3 Blowing
Func. Bicar. (pcr) 8 8 8 agent Gelation temp (.degree. C.) 200 210
210 Gelation Time (sec.) 120 90 120 Thickness (mm) 2.55 2.50 3.07
Expansion ratio (%) 340 330 410 Density (g/cm.sup.3) 0.4 0.42
0.37
Example 16-17 (in Accordance with Invention)
Functionalization Additive=Glycerol Monostearate
[0499] One sample of functionalized sodium bicarbonate was prepared
by extrusion of sodium bicarbonate particles with glycerol
monostearate (GMS) as the functionalization additive, and then
milling. Another sample of functionalized sodium bicarbonate was
prepared by spray agglomeration of sodium bicarbonate particles
with GMS, and then milling. The functionalized sodium bicarbonate
samples are identified as Example 16A (spray agglomerated with 25
wt % GMS) and Example 17A (extruded with 10 wt % GMS)
[0500] For Examples 16-17, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 7, where "pcr" means
parts by weight of PVC resin.
TABLE-US-00008 TABLE 7 Functionalization Additive = glycerol
monostearate Example 16 17 Functionalized Ex. 16A Ex. 17A
Bicarbonate Funct. Method Spray Agglomeration/milling
Extrusion/milling Funct. additive 25 wt % glycerol monostearate 10
wt % GMS D10/D50/D90 (.mu.m) 7.8/29/162 10/41/97 Plastisol Ex. 16
p1 16 p2 16 p3 16 p4 16 p5 16 p6 17 p1 17 p2 17 p3 PVC resin 367 NF
(pcr) 100 100 100 100 100 100 100 100 100 Filler CaCO.sub.3 (pcr)
120 120 120 120 120 120 120 120 120 Plastisizer Palatinol N (pcr)
80 80 80 80 80 80 80 80 80 Defoamer BYK3155 (pcr) -- -- -- 3 3 3 3
3 3 Blowing agent Func. Bicar. (pcr) 8 8 8 8 8 8 8 8 8 Gelation
temp (.degree. C.) 200 210 210 200 210 210 200 210 210 Gelation
Time (sec.) 90 90 120 90 90 120 120 90 120 Thickness (mm) 2.23 2.31
2.03 2.47 2.49 2.54 2.57 2.78 2.45 Expansion rate (%) 300 310 270
330 330 340 340 370 330 Density (g/cm.sup.3) 0.52 0.49 0.58 0.46
0.44 0.42 0.43 0.39 0.44
Example 18 (in Accordance with Invention)
Functionalization Additive=Eudragit RL 30D (poly(meth)acrylate)
[0501] One sample of functionalized sodium bicarbonate was prepared
by extrusion of sodium bicarbonate particles with a
poly(meth)acrylate under the brandname of Eudragit.RTM. RL 30D
available from Evonik which represents a polymer as
functionalization additive, and then milling. The functionalized
sodium bicarbonate sample is identified as Example 18A (4 wt %
Eudragit.RTM. RL 30D).
[0502] For Example 18, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after
[0503] Werner Mathis oven heating over the initial thickness of the
spread coated layer (here about 0.75 mm) before it passed the
Werner Mathis oven heating. The specific components and amounts in
each plastisol, the oven temperature, the time for gelation, the
thickness of the foamed product after oven heating, the expansion
ratio and the density of the PVC foams are provided in TABLE 8,
where "pcr" means parts by weight of PVC resin.
TABLE-US-00009 TABLE 8 Functionalization Additive = Eudragit .RTM.
RL 30D (organic polymer additive) Example 18 Functionalized Ex. 18A
Bicarbonate Funct. Method Extrusion/milling Funct. Additive 4 wt %
Eudragit .RTM. RL 30D D10/D50/D90 (.mu.m) 6.9/30/75 Plastisol Ex.
18 p1 18 p2 18 p3 18 p4 PVC resin 367 NF (pcr) 100 100 100 100
Filler CaCO.sub.3 (pcr) 120 120 120 120 Plastisizer Palatinol N
(pcr) 80 80 80 80 Defoamer BYK3155 (pcr) 3 3 3 3 Blowing Func.
Bicar. (pcr) 8 8 8 8 agent Gelation temp (.degree. C.) 200 210 210
210 Gelation Time (sec.) 90 60 90 120 Thickness (mm) 2.41 2.56 3.24
2.53 Expansion ratio (%) 320 340 430 340 Density (g/cm.sup.3) 0.45
0.47 0.33 0.42
Examples 19-20 (in Accordance with Invention)
Functionalization Additive=Epoxidized Soy Bean Oil
[0504] Two samples of functionalized sodium bicarbonate were
prepared by extrusion of sodium bicarbonate particles with an
epoxidized soy bean oil (sold as HSE Drapex 39 and 392 from Galata
Chemicals) which represents the functionalization additive, and
then milling. The epoxidized soybean oil is a vinyl additive which
can be used as heat stabilizer. The functionalized sodium
bicarbonate samples are identified as Example 19A (2 wt % HSE
Drapex 392) and Example 20A (2 wt % HSE Drapex 39).
[0505] For Examples 19-20, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 9, where "pcr" means
parts by weight of PVC resin.
TABLE-US-00010 TABLE 9 Functionalization Additive = epoxidized soy
bean oil Example 19 20 Functionalized Ex. 19A Ex. 20A Bicarbonate
Funct. Method Extrusion/milling Extrusion/milling Funct. additive 2
wt % HSE Drapex 392 2 wt % HSE Drapex 39 D10/D50/D90 (.mu.m)
5.4/25/61 -- Plastisol Ex. 19 p1 19 p2 19 p3 19 p4 20 p1 20 p2 20
p3 PVC resin 367 NF (pcr) 100 100 100 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 120 120 120 Plastisizer Palatinol
N (pcr) 80 80 80 80 80 80 80 Defoamer BYK3155 (pcr) 3 3 3 3 3 3 3
Blowing agent Func. Bicar. (pcr) 8 8 8 8 8 8 8 Gelation temp
(.degree. C.) 200 200 210 210 200 210 210 Gelation Time (sec.) 90
120 90 120 120 90 120 Thickness (mm) 2.33 2.44 2.77 2.29 2.33 2.91
2.53 Expansion ratio (%) 310 330 370 310 310 390 340 Density
(g/cm.sup.3) 0.48 0.48 0.38 0.49 0.47 0.41 0.47
Example 21 (in Accordance with Invention)
Functionalization Additive=Arabic Gum
[0506] One sample of functionalized sodium bicarbonate was prepared
by spray coating sodium bicarbonate particles in a fluidized bed
with arabic gum as functionalization additive, and then milling.
The functionalized sodium bicarbonate sample is identified as
Example 21A (20 wt % arabic gum).
[0507] For Example 21, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after
[0508] Werner Mathis oven heating over the initial thickness of the
spread coated layer (here about 0.75 mm) before it passed the
Werner Mathis oven heating. The specific components and amounts in
each plastisol, the oven temperature, the time for gelation, the
thickness of the foamed product after oven heating, the expansion
ratio and the density of the PVC foams are provided in TABLE 10.
"pcr" in TABLE 10 means parts by weight of resin.
TABLE-US-00011 TABLE 10 Functionalization Additive = arabic gum
Example 21 Functionalized Ex. 21A Bicarbonate Funct. Method Spray
coating in fluidized bed/milling Funct. additive 20 wt % Arabic gum
D10/D50/D90 (.mu.m) 6.2/29/93 Plastisol Ex. 21 p1 21 p2 21 p3 PVC
resin 367 NF (pcr) 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120
Plastisizer Palatinol N (pcr) 80 80 80 Defoamer BYK3155 (pcr) 3 3 3
Blowing agent Func. Bicar. (pcr) 8 8 8 Gelation temp (.degree. C.)
200 210 210 Gelation Time (sec.) 120 90 120 Thickness (mm) 2.73
2.49 2.52 Expansion ratio (%) 360 330 340 Density (g/cm.sup.3) 0.42
0.45 0.43
Example 22 (in Accordance with Invention)
Functionalization Additive=Linoleic Acid
[0509] One sample of functionalized sodium bicarbonate was prepared
by co-milling of sodium bicarbonate particles with linoleic acid as
functionalization additive. The functionalized sodium bicarbonate
sample is identified as Example 22A (0.8 wt % linoleic acid).
[0510] For Example 22, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after Werner Mathis
oven heating over the initial thickness of the spread coated layer
(here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 11, where "pcr"
means parts by weight of PVC resin.
TABLE-US-00012 TABLE 11 Functionalization Additive = linoleic acid
Example 22 Functionalized Ex. 22A Bicarbonate Funct. Method
Co-milling Funct. additive 0.8 wt % linoleic acid D10/D50/D90
(.mu.m) 2.8/12/25 Plastisol Ex. 22 p1 22 p2 22 p3 22 p4 22 p4 PVC
resin 367 NF (pcr) 100 100 100 100 100 Filler CaCO.sub.3 (pcr) 120
120 120 120 120 Plastisizer Palatinol N (pcr) 80 80 80 80 80
Defoamer BYK3155 (pcr) -- 3 3 3 3 Blowing agent Func. Bicar. (pcr)
8 8 8 8 8 Gelation temp (.degree. C.) 210 200 200 210 210 Gelation
Time (sec.) 90 90 120 90 120 Thickness (mm) 2.11 2.49 2.35 2.66
2.01 Expansion ratio (%) 280 330 310 350 270 Density (g/cm.sup.3)
0.57 0.44 0.49 0.40 0.57
Examples 23-24 (in Accordance with Invention)
Functionalization Additive=Maltodextrin
[0511] Two samples of functionalized sodium bicarbonate were
prepared by spray coating of sodium bicarbonate particles in a
fluidized bed with maltodextrin as the functionalization additive,
and then milling. The functionalized sodium bicarbonate samples are
identified as Example 23A and Example 24A (20 wt %
maltodextrin).
[0512] For Examples 23-24, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 12, where "pcr"
means parts by weight of resin.
TABLE-US-00013 TABLE 12 Functionalization Additive = maltodextrin
Example 23 24 Functionalized Ex. 23A Ex. 24A Bicarbonate Funct.
Method Spray Coating/milling Spray Coating/milling Funct. additive
20 wt % Maltodextrin 20 wt % Maltodextrin D10/D50/D90 (.mu.m)
4.9/25/82 151/249/403 Plastisol Ex. 23 p1 23 p2 23 p3 23 p4 24 p1
24 p2 PVC resin 367 NF (pcr) 100 100 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 120 120 Plastisizer Palatinol N
(pcr) 80 80 80 80 80 80 Defoamer BYK3155 (pcr) -- -- -- 3 -- 3
Blowing agent Func. Bicar. (pcr) 8 8 8 8 8 8 Gelation temp
(.degree. C.) 200 210 210 210 210 210 Gelation Time (sec.) 120 90
120 120 120 120 Thickness (mm) 2.17 2.43 2.24 2.42 2.14 2.03
Expansion ratio (%) 290 320 300 320 290 270 Density (g/cm.sup.3)
0.52 0.47 0.49 0.45 0.52 0.54
Examples 25-26 (in Accordance with Invention)
Functionalization Additive=Polyethylene Glycol (PEG400)
[0513] Two samples of functionalized sodium bicarbonate were
prepared by extrusion of sodium bicarbonate particles with a
polyethylene glycol of low molecular weight (<1000 g/mol):
PEG400 as the functionalization additive. The functionalized sodium
bicarbonate samples are identified as Example 25A (20 wt % PEG400)
and Example 26A (10 wt % PEG400).
[0514] For Examples 25-26, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 13, where "pcr"
means parts by weight of PVC resin.
TABLE-US-00014 TABLE 13 Functionalization Additive = Polyethylene
Glycol (PEG400) Example 25 26 Functionalized Ex. 25A Ex. 26A
Bicarbonate Funct. Method extrusion extrusion Funct. additive 20 wt
% PEG400 10 wt % PEG400 D10/D50/D90 (.mu.m) -- -- Plastisol Ex. 25
p1 25 p2 25 p3 25 p4 26 p1 26 p2 PVC resin 367 NF (pcr) 100 100 100
100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 120 120 120
Plastisizer Palatinol N (pcr) 80 80 80 80 80 80 Defoamer BYK3155
(pcr) -- -- -- -- -- -- Blowing agent Func. Bicar. (pcr) 10 10 10
10 9 9 Gelation temp (.degree. C.) 200 200 210 210 200 210 Gelation
Time (sec.) 90 120 90 120 90 90 Thickness (mm) 2.52 2.14 2.80 2.62
2.54 2.43 Expansion ratio (%) 340 290 370 350 340 320 Density
(g/cm.sup.3) 0.44 0.51 0.38 0.41 0.44 0.44
Examples 27-31 (in Accordance with Invention)
Functionalization Additive=Polyethylene Glycol (PEG4000)
[0515] Three samples of functionalized sodium bicarbonate were
prepared by extrusion of sodium bicarbonate particles with a
polyethylene glycol of high molecular weight (>1000): PEG 4000,
and then milling. Two other sample of functionalized sodium
bicarbonate were prepared by spray coating of sodium bicarbonate
particles in a fluidized bed with PEG4000, and then milling. The
functionalized sodium bicarbonate samples are identified as Example
27A (extruded with 7 wt % PEG4000), Example 28A (extruded with 10
wt % PEG4000), Example 29A (extruded with 3 wt % PEG4000), Example
30A (spray coated with 10 wt % PEG4000), and Example 31A (spray
coated with 20 wt % PEG4000).
[0516] For Examples 27-31, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 14. "pcr" in TABLE
14 means parts by weight of resin.
TABLE-US-00015 TABLE 14 Functionalization Additive = Polyethylene
Glycol (PEG4000) Example 27 28 Functionalized Ex. 27A Ex. 28A
Bicarbonate Funct. Method Extrusion/milling Extrusion/milling
Funct. additive 7 wt % PEG4000 10 wt % PEG4000 D10/D50/D90 (.mu.m)
4.9/22/57 6.9/32/81 Plastisol Ex. 27 p1 27 p2 27 p3 27 p4 28 p1 28
p2 28 p3 PVC resin 367 NF (pcr) 100 100 100 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 120 120 120 Plastisizer Palatinol
N (pcr) 80 80 80 80 80 80 80 Defoamer BYK3155 (pcr) 3 3 3 3 3 3 3
Blowing agent Func. Bicar. (pcr) 8 8 8 8 8 8 8 Gelation temp
(.degree. C.) 200 200 210 210 200 210 210 Gelation Time (sec.) 90
120 90 120 120 90 120 Thickness (mm) 2.16 2.29 2.97 2.39 2.46 2.89
2.19 Expansion ratio (%) 290 310 400 320 330 390 290 Density
(g/cm.sup.3) 0.54 0.50 0.37 0.43 0.43 0.37 0.48 Example 29 30
Functionalized Ex. 29A Ex. 30A Bicarbonate Funct. Method
Extrusion/milling Spray Coating/milling Funct. additive 3 wt %
PEG4000 10 wt % PEG4000 D10/D50/D90 (.mu.m) 5.2/25/61 5.6/26/65
Plastisol Ex. 29 p1 29 p2 29 p3 30 p1 30 p2 30 p3 30 p4 PVC resin
367 NF (pcr) 100 100 100 100 100 100 100 Filler CaCO.sub.3 (pcr)
120 120 120 120 120 120 120 Plastisizer Palatinol N (pcr) 80 80 80
80 80 80 80 Defoamer BYK3155 (pcr) 3 3 3 3 3 3 3 Blowing agent
Func. Bicar. (pcr) 8 8 8 8 8 8 8 Gelation temp (.degree. C.) 200
210 210 200 200 210 210 Gelation Time (sec.) 120 90 120 90 120 90
120 Thickness (mm) 2.70 3.07 2.44 2.06 2.38 2.98 2.33 Expansion
ratio (%) 360 410 330 270 320 400 310 Density (g/cm.sup.3) 0.43
0.38 0.44 0.52 0.44 0.36 0.45 Example 31 Functionalized Ex. 31A
Bicarbonate Funct. Method Spray Coating/milling Funct. additive 20
wt % PEG4000 D10/D50/D90 (.mu.m) 6.6/29/75 Plastisol Ex. 31 p1 31
p2 31 p3 31 p4 PVC resin 367 NF (pcr) 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 Plastisizer Palatinol N (pcr) 80
80 80 80 Defoamer BYK3155 (pcr) -- 3 3 3 Blowing agent Func. Bicar.
(pcr) 8 8 8 8 Gelation temp (.degree. C.) 210 200 210 210 Gelation
Time (sec.) 90 120 90 120 Thickness (mm) 2.04 2.46 2.66 2.30
Expansion ratio (%) 270 330 350 310 Density (g/cm.sup.3) 0.56 0.46
0.43 0.49
Examples 32-34 (in Accordance with Invention)
Functionalization Additive=Polyvinylalcohol (PVOH)
[0517] Three samples of functionalized sodium bicarbonate were
prepared by extrusion of sodium bicarbonate particles with
polyvinylalcohol (PVOH), an organic polymer as the
functionalization additive, and then milling. The functionalized
sodium bicarbonate samples are identified as Example 32A (extruded
with 5 wt % PVOH), Example 33A (extruded with 10 wt % PVOH),
Example 34A (extruded with 35 wt % PVOH).
[0518] For Examples 32-34, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 15. "pcr" in TABLE
15 means parts by weight of resin.
TABLE-US-00016 TABLE 15 Functionalization Additive =
polyvinylalcohol (PVOH) Example 32 33 34 Functionalized Ex. 32A Ex.
33A Ex. 34A Bicarbonate Funct. Method Extrusion/milling
Extrusion/milling Extrusion/milling Funct. additive 5 wt % PVOH 10
wt % PVOH 35 wt % PVOH D10/D50/D90 (.mu.m) -- 4.3/55/173 4/45/157
Plastisol Ex. 32 p1 32 p2 33 p1 33 p2 33 p3 33 p4 34 p1 34 p2 34 p3
PVC resin 367 NF (pcr) 100 100 100 100 100 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 120 120 120 120 120 Plastisizer
Palatinol N (pcr) 80 80 80 80 80 80 80 80 80 Defoamer BYK3155 (pcr)
3 3 3 3 3 3 3 3 3 Blowing agent Func. Bicar. (pcr) 8 8 8 8 8 8 8 8
8 Gelation temp (.degree. C.) 200 210 200 200 210 210 200 210 210
Gelation Time (sec.) 120 120 90 120 90 120 120 90 120 Thickness
(mm) 2.04 2.61 2.06 2.51 2.57 2.49 2.31 2.32 2.32 Expansion ratio
(%) 270 350 270 330 340 330 310 310 310 Density (g/cm.sup.3) 0.54
0.41 0.58 0.44 0.43 0.45 0.46 0.48 0.49
Examples 35-36 (in Accordance with Invention)
Functionalization Additive=Lauric Acid
[0519] Two samples of functionalized sodium bicarbonate were
prepared by extrusion of sodium bicarbonate particles with lauric
acid, and then milling. The functionalized sodium bicarbonate
samples are identified as Examples 35A and 36A (10 wt % lauric
acid).
[0520] For Examples 35-36, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 16, wherein "pcr"
means parts by weight of PVC resin.
TABLE-US-00017 TABLE 16 FunctionalizationAdditive = Laurie acid
Example 35 36 Functionalized Ex. 35A Ex. 36A Bicarbonate Funct.
Method Extrusion/milling Extrusion/milling Funct. Additive 10 wt %
lauric acid 10 wt % lauric acid D10/D50/D90 (.mu.m) 3.5/20/55
10/50/127 Plastisol Ex. 35 p1 35 p2 35 p3 35 p4 36 p1 36 p2 36 p3
PVC resin 367 NF (pcr) 100 100 100 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 120 120 120 Plastisizer Palatinol
N (pcr) 80 80 80 80 80 80 80 Defoamer BYK3155 (pcr) 3 3 3 -- 3 3 --
Blowing agent Func. Bicar. (pcr) 8 8 8 8 8 8 8 Gelation temp
(.degree. C.) 200 210 210 210 200 210 210 Gelation Time (sec.) 120
90 120 90 120 120 90 Thickness (mm) 2.88 2.83 3.28 2.09 2.23 2.96
2.11 Expansion ratio (%) 380 380 440 280 300 390 280 Density
(g/cm.sup.3) 0.37 0.39 0.36 0.53 0.50 0.37 0.52
Examples 37-39 (in Accordance with Invention)
Functionalization Additive=Rosin Acid
[0521] Three samples of functionalized sodium bicarbonate were
prepared by co-grinding (co-milling) sodium bicarbonate particles
with rosin acid. The samples are identified as Examples 37A (1 wt %
rosin acid), 38A (2 wt % rosin acid), 39A (10 wt % rosin acid).
[0522] For Examples 37-39, PVC Plastisol compositions were prepared
in a Dispermat apparatus. In each example, the components of the
plastisols were dispersed on a high speed mixer and then mixed and
de-aerated under vacuum. The resulting liquid PVC pastes
(plastisols) of Example 14 are in each case spread coated at a
thickness of about 0.75 mm on a piece of paper (Claire Fontaine)
and heated in a Thermosol Werner Mathis oven set at 200 or
210.degree. C. for 90 or 120 seconds. The expansion ratio was
calculated as the ratio of the thickness of the foamed product
after Werner Mathis oven heating over the initial thickness of the
spread coated layer (here about 0.75 mm) before it passed the
Werner Mathis oven heating. The specific components and amounts in
each plastisol, the oven temperature, the time for gelation, the
thickness of the foamed product after oven heating, the expansion
ratio and the density of the PVC foams are provided in TABLE 17,
where "pcr" means parts by weight of PVC resin.
TABLE-US-00018 TABLE 17 Functionalization Additive = rosin acid
Example 37 Functionalized Ex. 37A Bicarbonate Funct. Method
Co-milling Funct. additive 1 wt % rosin acid D10/D50/D90 (.mu.m)
3.3/19/56 Plastisol Ex. 37 p1 37 p2 37 p3 37 p4 PVC resin 367 NF
(pcr) 100 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 120
Plastisizer Palatinol N (pcr) 80 80 80 80 Defoamer BYK3155 (pcr) 3
3 3 3 Blowing agent Func. Bicar. (pcr) 8 8 8 8 Gelation temp
(.degree. C.) 200 200 210 210 Gelation Time (sec.) 90 120 90 120
Thickness (mm) 2.35 2.13 2.77 2.34 Expansion ratio (%) 310 280 370
310 Density (g/cm.sup.3) 0.47 0.49 0.43 0.45 Example 38
Functionalized Ex. 38A Bicarbonate Funct. Method Co-milling Funct.
additive 2 wt % rosin acid D10/D50/D90 (.mu.m) 1.7/10/24 Plastisol
Ex. 38 p1 38 p2 38 p3 38 p4 38 p5 38 p6 PVC resin 367 NF (pcr) 100
100 100 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 120 120 120
Plastisizer Palatinol N (pcr) 80 80 80 80 80 80 Defoamer BYK3155
(pcr) -- -- 3 3 3 3 Blowing agent Func. Bicar. (pcr) 8 8 8 8 8 8
Gelation temp (.degree. C.) 200 210 200 200 210 210 Gelation Time
(sec.) 90 90 90 120 90 120 Thickness (mm) 2.15 2.24 2.37 3.0 3.29
3.00 Expansion ratio (%) 290 300 320 400 440 400 Density
(g/cm.sup.3) 0.53 0.50 0.47 0.36 0.36 0.39 Example 39
Functionalized Ex. 39A Bicarbonate Funct. Method Co-milling Funct.
additive 10 wt % rosin acid D10/D50/D90 (.mu.m) 1.5/7.7/17.7
Plastisol Ex. 39 p1 39 p2 39 p3 39 p4 39 p5 39 p6 PVC resin 367 NF
(pcr) 100 100 100 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120
120 120 120 Plastisizer Palatinol N (pcr) 80 80 80 80 80 80
Defoamer BYK3155 (pcr) -- -- -- 3 3 3 Blowing agent Func. Bicar.
(pcr) 8 8 8 8 8 8 Gelation temp (.degree. C.) 200 210 210 200 210
210 Gelation Time (sec.) 120 90 120 120 90 120 Thickness (mm) 2.88
2.61 3.20 2.84 2.64 3.54 Expansion ratio (%) 380 350 430 380 350
470 Density (g/cm.sup.3) 0.38 0.43 0.35 0.38 0.42 0.32
Example 40 (in Accordance with Invention)
Functionalization Additive=Starch
[0523] One sample of functionalized sodium bicarbonate was prepared
by spray coating of sodium bicarbonate particles in a fluidized bed
with starch, and then milling. The functionalized sodium
bicarbonate sample is identified as Example 40A (5 wt %
starch).
[0524] For Example 40, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after Werner Mathis
oven heating over the initial thickness of the spread coated layer
(here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 18. "pcr" in TABLE
18 means parts by weight of resin.
TABLE-US-00019 TABLE 18 Functionalization Additive = Starch Example
40 Functionalized Bicarbonate Ex. 40A Funct. Method Spray
Coating/milling Funct. Additive 5 wt % starch D10/D50/D90 (.mu.m)
4.3/23/67 Plastisol Ex. 40 p1 40 p2 40 p3 PVC resin 367 NF (pcr)
100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 Plastisizer
Palatinol N (pcr) 80 80 80 Defoamer BYK3155 (pcr) 3 3 3 Blowing
agent Func. Bicar. (pcr) 8 8 8 Gelation temp (.degree. C.) 200 210
210 Gelation Time (sec.) 120 90 120 Thickness (mm) 2.88 2.59 2.60
Expansion ratio (%) 380 350 350 Density (g/cm.sup.3) 0.38 0.42
0.41
Examples 41-42 (in Accordance with Invention)
Functionalization Additive=Stearic Acid
[0525] Two samples of functionalized sodium bicarbonate was
prepared by extrusion of sodium bicarbonate particles with stearic
acid, and then milling. The functionalized sodium bicarbonate
sample is identified as Examples 41A and 42A (5 wt % stearic
acid).
[0526] For Examples 41-42, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 19, where "pcr" in
means parts by weight of PVC resin.
TABLE-US-00020 TABLE 19 Functionalization Additive = Stearic acid
Example 41 42 Functionalized Ex. 41A Ex. 42A Bicarbonate Funct.
Method Extrusion/milling Extrusion/milling Funct. Additive 5 wt %
stearic acid 5 wt % stearic acid D10/D50/D90 (.mu.m) 1.3/22/85
2.9/22/55 Plastisol Ex. 41 p1 41 p2 41 p3 42 p1 42 p2 42 p3 42 p4
42 p5 42 p6 42 p7 PVC resin 367 NF (pcr) 100 100 100 100 100 100
100 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 120 120 120 120
120 120 120 Plastisizer Palatinol N (pcr) 80 80 80 80 80 80 80 80
80 80 Defoamer BYK3155 (pcr) 3 3 3 -- -- -- -- 3 3 3 Blowing agent
Func. Bicar. (pcr) 8 8 8 8 8 8 8 8 8 8 Gelation temp (.degree. C.)
200 210 210 200 210 210 210 200 210 210 Gelation Time (sec.) 120 90
120 90 120 90 120 120 90 120 Thickness (mm) 2.54 2.30 2.44 2.02
2.01 2.51 2.17 2.45 2.09 2.90 Expansion ratio (%) 340 310 330 270
270 330 290 270 280 390 Density (g/cm.sup.3) 0.64 0.50 0.47 0.56
0.57 0.45 0.52 0.57 0.54 0.39
Examples 43-44 (in Accordance with Invention)
Functionalization Additive=Polyoxyalkylene Compound (Polymer)
[0527] Two samples of functionalized sodium bicarbonate were
prepared by extrusion of sodium bicarbonate particles with a
polyoxyalkylene compound as the functionalization additive. The
polyoxyalkylene compound is a product sold by BYK under the
brandname BYK 3155 which may be used as an air release agent. The
functionalized sodium bicarbonate samples are identified as Example
43A (10 wt % BYK 3155) and Example 44A (20 wt % BYK 3155).
[0528] For Examples 43-44, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 20, where "pcr"
means parts by weight of PVC resin.
TABLE-US-00021 TABLE 20 Functionalization Additive =
Polyoxyalkylene compound (BYK3155) Example 43 44 Functionalized Ex.
43A Ex. 44A Bicarbonate Funct. Method extrusion extrusion Funct.
additive 10 wt % BYK3155 20 wt % BYK3155 -- -- -- Plastisol Ex. 43
p1 43 p2 43 p3 43 p4 44 p1 44 p2 44 p3 PVC resin 367 NF (pcr) 100
100 100 100 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 120 120
120 120 Plastisizer Palatinol N (pcr) 80 80 80 80 80 80 80 Defoamer
BYK3155 (pcr) -- -- -- -- -- -- -- Blowing agent Func. Bicar. (pcr)
9 9 9 9 10 10 10 Gelation temp (.degree. C.) 200 200 210 210 200
210 210 Gelation Time (sec.) 90 120 90 120 120 90 120 Thickness
(mm) 2.03 2.06 2.30 2.08 2.43 2.60 2.45 Expansion ratio (%) 270 270
310 280 320 350 330 Density (g/cm.sup.3) 0.52 0.54 0.47 0.51 0.45
0.41 0.44
Examples 45-46 (in Accordance with Invention)
With Two Functionalization Additives=Rosin Acid; PEG400
[0529] Two samples of functionalized sodium bicarbonate were
prepared by applying two different functionalization additives
(rosin acid, PEG400) added sequentially using two different methods
of functionalization (co-grinding, extrusion). First the sodium
bicarbonate particles were functionalized by co-grinding them with
rosin acid as a first functionalization additive, and then the
first-functionalized particles were functionalized by extruding
them with PEG400 as a second functionalization additive to form
second-functionalized particles. The samples are identified as
Example 45A (9 wt % rosin acid, 10 wt % PEG400) and Example 46A (8
wt % rosin acid, 20 wt % PEG400).
[0530] For Examples 45-46, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 21 where "pcr" means
parts by weight of PVC resin.
TABLE-US-00022 TABLE 21 Two Functionalization Additives = Rosin
acid, PEG400 added sequentially Example 45 46 Functionalized Ex.
45A Ex. 46A Bicarbonate 1.sup.st Funct. Method co-milling
co-milling 1.sup.st Funct. additive 10 wt % rosin acid 10 wt %
rosin acid 2.sup.nd Funct. Method extrusion extrusion 2.sup.nd
Funct. additive 10 wt % PEG400 20 wt % PEG400 Resulting 81 wt % Na
bicarbonate/ 72 wt % Na bicarbonate/ Composition 9 wt % rosin acid/
8 wt % rosin acid/ 10 wt % PEG400 20 wt % PEG400 Plastisol Ex. 45
p1 45 p2 45 p3 45 p4 46 pl 46 p2 46 p3 PVC resin 367 NF (pcr) 100
100 100 100 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 120 120
120 120 Plastisizer Palatinol N (pcr) 80 80 80 80 80 80 80 Defoamer
BYK3155 (pcr) -- -- -- -- -- -- -- Blowing agent Func. Bicar. (pcr)
9 9 9 9 10 10 10 Gelation temp (.degree. C.) 200 200 210 210 200
210 210 Gelation Time (sec.) 90 120 90 120 120 90 120 Thickness
(mm) 2.03 2.06 2.30 2.08 2.43 2.60 2.45 Expansion ratio (%) 270 270
310 280 320 350 330 Density (g/cm.sup.3) 0.52 0.54 0.47 0.51 0.45
0.41 0.44
Examples 47-48 (in Accordance with Invention)
With Two Functionalization Additives=Stearic Acid; PEG400
[0531] Two samples of functionalized sodium bicarbonate were
prepared by applying two different functionalization additives
(stearic acid, PEG400) added sequentially using two different
methods of functionalization (co-grinding, extrusion). First the
sodium bicarbonate particles were functionalized by co-grinding
them with stearic acid as a first functionalization additive, and
then the first-functionalized particles were functionalized by
extruding them with PEG400 as a second functionalization additive
to form second-functionalized particles. The samples are identified
as Example 47A (3.2 wt % stearic acid, 10 wt % PEG400) and Example
48A (2.8 wt % stearic acid, 20 wt % PEG400).
[0532] For Examples 47-48, the same method of preparation of the
PVC Plastisol compositions and preparation of PVC foams were used
as described for Example 14. The expansion ratio was calculated as
the ratio of the thickness of the foamed product after Werner
Mathis oven heating over the initial thickness of the spread coated
layer (here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio, and the
density of the PVC foams are provided in TABLE 22 where "pcr" means
parts by weight of PVC resin.
TABLE-US-00023 TABLE 22 Two Functionalization Additives = Stearic
acid, PEG400 added sequentially Example 47 48 Functionalized Ex.
47A Ex. 48A Bicarbonate 1.sup.st Funct. Method co-milling
co-milling 1.sup.st Funct. additive 3.5 wt % stearic acid 3.5 wt %
stearic acid 2.sup.nd Funct. Method extrusion extrusion 2.sup.nd
Funct. additive 10 wt % PEG400 20 wt % PEG400 Resulting 86.9 wt %
Na bicarbonate/ 77.2 wt % Na bicarbonate/ Composition 3.2 wt %
stearic acid/ 2.8 wt % stearic acid/ 10 wt % PEG400 20 wt % PEG400
Plastisol Ex. 47 p1 47 p2 47 p3 47 p4 47 p5 47 p6 47 p7 48 p1 48 p2
48 p3 48 p4 PVC resin 367 NF (pcr) 100 100 100 100 100 100 100 100
100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120 120 120 120 120 120
120 120 120 Plastisizer Palatinol N (pcr) 80 80 80 80 80 80 80 80
80 80 80 Defoamer BYK3155 (pcr) -- -- -- 3 3 3 3 -- -- -- --
Blowing agent Func. Bicar. (pcr) 9 9 9 9 9 9 9 10 10 10 10 Gelation
temp (.degree. C.) 200 210 210 200 200 210 210 200 200 210 200
Gelation Time (sec.) 90 90 120 90 120 90 120 90 120 90 120
Thickness (mm) 2.22 2.44 2.08 2.60 2.89 3.12 2.92 2.53 2.17 2.99
2.32 Expansion ratio (%) 300 330 280 350 390 420 390 340 290 400
310 Density (g/cm.sup.3) 0.51 0.45 0.53 0.42 0.38 0.35 0.39 0.44
0.52 0.38 0.49
Example 49 (in Accordance with Invention)
With One Functionalization Additive=Lauric Acid
With a Second Compound which Liberates CO2 Upon Heating (Second
Blowing Agent)=Citric Acid
[0533] One sample of functionalized sodium bicarbonate was prepared
by applying one functionalization additive (lauric acid) to a
mixture of sodium bicarbonate particles and powder of citric acid
(a second compound which liberates CO2 upon heating) to extrude the
mixture followed by milling extrudates to reduce the particle size
of the resulting functionalized bicarbonate particles
(extrusion/milling). First the sodium bicarbonate particles were
blended with citric acid powder in a weight ratio of 80 sodium
bicarbonate to 20 citric acid, then adding lauric acid to this
blend and subjecting the resulting mixture to extrusion, and then
milling. The samples are identified as Example 49A (19 wt % citric
acid, 5 wt % lauric acid).
[0534] For Example 49, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after Werner Mathis
oven heating over the initial thickness of the spread coated layer
(here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 23 where "pcr" means
parts by weight of PVC resin.
TABLE-US-00024 TABLE 23 With one Functionalization Additive =
lauric acid With one additional endothermic blowing agent = citric
acid Example 49 Functionalized Ex. 49A bicarbonate 1.sup.st blowing
agent 80 wt % sodium bicarbonate 2.sup.nd blowing agent 20 wt %
citric acid Method mixing 2.sup.nd Funct. additive 5 wt % lauric
acid Funct. Method Extrusion/milling Resulting Func. Bicar. 76 wt %
Na bicarbonate/19 wt % Composition citric acid/5 wt % lauric acid
D10/D50/D90 (.mu.m) 2.9/23/70 Plastisol Ex. 49 p1 49 p2 49 p3 49 p4
PVC resin 367 NF (pcr) 100 100 100 100 Filler CaCO.sub.3 (pcr) 120
120 120 120 Plastisizer Palatinol N (pcr) 80 80 80 80 Defoamer
BYK3155 (pcr) -- -- 3 3 Blowing Func. Bicar. (pcr) 8 8 8 8 agent
Gelation temp (.degree. C.) 200 210 200 210 Gelation Time (sec.)
120 120 120 120 Thickness (mm) 2.15 2.29 2.28 2.13 Expansion ratio
(%) 290 310 300 280 Density (g/cm.sup.3) 0.51 0.48 0.48 0.50
Example 50 (in Accordance with Invention)
With One Functionalization Additive=Lauric Acid
With a Second Compound which Liberates CO2 Upon Heating (Second
Blowing Agent)=Fumaric Acid
[0535] One sample of functionalized sodium bicarbonate was prepared
by applying one functionalization additive (lauric acid) to a
mixture of sodium bicarbonate particles and powder of fumaric acid
(a second compound which liberates CO2 upon heating) to extrude the
mixture followed by milling extrudates to reduce the particle size
of the resulting functionalized bicarbonate particles
(extrusion/milling). First the sodium bicarbonate particles were
blended with fumaric acid powder in a weight ratio of 80 sodium
bicarbonate to 20 fumaric acid, then adding lauric acid to this
blend and subjecting the resulting mixture to extrusion and then
milling. The sample is identified as Example 50A (19 wt % fumaric
acid, 5 wt % lauric acid).
[0536] For Example 50, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after Werner Mathis
oven heating over the initial thickness of the spread coated layer
(here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 24, where "pcr"
means parts by weight of PVC resin.
TABLE-US-00025 TABLE 24 With one Functionalization Additive =
lauric acid With a second endothermic blowing agent = fumaric acid
Example 50 Functionalized Ex. 50A bicarbonate 1.sup.st blowing
agent 80 wt % sodium bicarbonate 2.sup.nd blowing agent 20 wt %
fumaric acid Method mixing 2.sup.nd Funct. additive 5 wt % lauric
acid Funct. Method Extrusion/milling Resulting Func. Bicar. 76 wt %
Na bicarbonate/19 wt % Composition fumaric acid/5 wt % lauric acid
D10/D50/D90 (.mu.m) 2.7/21/79 Plastisol Ex. 50 p1 50 p2 50 p3 PVC
resin 367 NF (pcr) 100 100 100 Filler CaCO.sub.3 (pcr) 120 120 120
Plastisizer Palatinol N (pcr) 80 80 80 Defoamer BYK3155 (pcr) 3 3 3
Blowing Func. Bicar. (pcr) 8 8 8 agent Gelation temp (.degree. C.)
200 210 210 Gelation Time (sec.) 120 90 120 Thickness (mm) 2.56
2.10 2.29 Expansion ratio (%) 340 280 310 Density (g/cm.sup.3) 0.50
0.56 0.49
Example 51 (in Accordance with Invention)
With One Functionalization Additive=Maltodextrin
With a Second Blowing Agent=Citric Acid
[0537] One sample of functionalized sodium bicarbonate was prepared
by applying one functionalization additive (maltodextrin) to a
mixture of sodium bicarbonate particles and powder of citric acid
(a second blowing agent compound which liberates CO2 upon heating)
to extrude the mixture and then mill. First the sodium bicarbonate
particles were blended with citric acid powder in a weight ratio of
80 sodium bicarbonate to 20 citric acid, then adding maltodextrin
to this blend and subjecting the resulting mixture to extrusion,
and then milling. The sample is identified as Example 48A (16 wt %
citric acid, 20 wt % maltodextrin).
[0538] For Example 51, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after Werner Mathis
oven heating over the initial thickness of the spread coated layer
(here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 25, where "pcr"
means parts by weight of resin.
TABLE-US-00026 TABLE 25 With one Functionalization Additive =
maltodextrin With one additional endothermic blowing agent = citric
acid Example 51 Functionalized bicarbonate Ex. 51A 1.sup.st blowing
agent 80 wt % sodium bicarbonate 2.sup.nd blowing agent 20 wt %
citric acid Method mixing 2.sup.nd Funct. additive 20 wt %
maltodextrin Funct. Method Extrusion/milling Resulting Func. Bicar.
64 wt % Na bicar/16 wt % citric Composition acid/20 wt %
maltodextrin D10/D50/D90 (.mu.m) 9.9/37/98 Plastisol Ex. 51 p1 51
p2 PVC resin 367 NF (pcr) 100 100 Filler CaCO.sub.3 (pcr) 120 120
Plastisizer Palatinol N (pcr) 80 80 Defoamer BYK3155 (pcr) -- 3
Blowing Func. Bicar. (pcr) 8 8 agent Gelation temp (.degree. C.)
210 210 Gelation Time (sec.) 90 120 Thickness (mm) 2.18 2.07
Expansion ratio (%) 290 280 Density (g/cm.sup.3) 0.51 0.53
Example 52 (in Accordance with Invention)
With One Functionalization Additive=Epoxidized Soybean Oil
With a Second Blowing Agent=Citric Acid
[0539] One sample of functionalized sodium bicarbonate was prepared
by applying one functionalization additive (epoxidized soy bean oil
sold as HSE Drapex 392 from Galata Chemicals)) to a mixture of
sodium bicarbonate particles and powder of citric acid (a second
blowing agent compound which liberates CO2 upon heating) to extrude
the mixture, and then mill. First the sodium bicarbonate particles
were blended with citric acid powder in a weight ratio of 80 sodium
bicarbonate to 20 citric acid, then adding the epoxidized soybean
oil (HSE Drapex 392) to this blend and subjecting the resulting
mixture to extrusion, and then milling. The sample is identified as
Example 52A (19 wt % citric acid, 5 wt % maltodextrin).
[0540] For Example 52, the same method of preparation of the PVC
Plastisol compositions and preparation of PVC foams were used as
described for Example 14. The expansion ratio was calculated as the
ratio of the thickness of the foamed product after Werner Mathis
oven heating over the initial thickness of the spread coated layer
(here about 0.75 mm) before it passed the Werner Mathis oven
heating. The specific components and amounts in each plastisol, the
oven temperature, the time for gelation, the thickness of the
foamed product after oven heating, the expansion ratio and the
density of the PVC foams are provided in TABLE 26 where "pcr" means
parts by weight of PVC resin.
TABLE-US-00027 TABLE 26 With one Functionalization Additive =
epoxidized soybean oil With one additional endothermic blowing
agent = citric acid Example 52 Functionalized bicarbonate Ex. 52A
1.sup.st blowing agent 80 wt % sodium bicarbonate 2.sup.nd blowing
agent 20 wt % citric acid Method mixing 2.sup.nd Funct. additive 5
wt % HSE Drapex 392 Funct. Method Extrusion/milling Resulting Func.
Bicar. 76 wt % Na bicar/19 wt % Composition citric acid/5 wt %
epoxidised soybean oil D10/D50/D90 (.mu.m) 9.9/37/98 Plastisol Ex.
52 p1 52 p2 PVC resin 367 NF (pcr) 100 100 Filler CaCO.sub.3 (pcr)
120 120 Plastisizer Palatinol N (pcr) 80 80 Defoamer BYK3155 (pcr)
3 3 Blowing agent Func. Bicar. (pcr) 8 8 Gelation temp (.degree.
C.) 200 210 Gelation Time (sec.) 120 90 Thickness (mm) 2.14 2.30
Expansion ratio (%) 290 310 Density (g/cm.sup.3) 0.53 0.47
Example 53 (not in Accordance with Invention)
Functionalization Additive=None
[0541] A commercial sodium bicarbonate (SB/03 from Solvay) was
milled to reduce the particle size. The sample is identified as
Example 53A (without functionalization additive).
[0542] For Example 53, PVC Plastisol compositions were prepared in
a Dispermat apparatus. In each example, the components of the
plastisols were dispersed on a high speed mixer and then mixed and
de-aerated under vacuum. The resulting liquid PVC pastes
(plastisols) are in each case spread coated at a thickness of about
0.75 mm on a piece of paper (Claire Fontaine) and heated in a
Thermosol Werner Mathis oven set at 200 or 210.degree. C. for 90 or
120 seconds. The expansion ratio was calculated as the ratio of the
thickness of the foamed product after Werner Mathis oven heating
over the initial thickness of the spread coated layer (here about
0.75 mm) before it passed the Werner Mathis oven heating. The
specific components and amounts in each plastisol, the oven
temperature, the time for gelation, the thickness of the foamed
product after oven heating, the expansion ratio and the density of
the PVC foams are provided in TABLE 27, where "pcr" means parts by
weight of PVC resin.
TABLE-US-00028 TABLE 27 Without functionalization additive Without
additional endothermic blowing agent Example 53 Non-Functionalized
Ex. 53A bicarbonate D10/D50/D90 (.mu.m) 1.3/7/16 Plastisol Ex. 53
p1 53 p2 53 p3 53 p4 PVC resin 367 NF (pcr) 100 100 100 100 Filler
CaCO.sub.3 (pcr) 120 120 120 120 Plastisizer Palatinol N (pcr) 80
80 80 80 Defoamer BYK3155 (pcr) -- -- -- -- Blowing Non-Func.
Bicar. (pcr) 8 8 8 8 agent Gelation temp (.degree. C.) 200 200 210
210 Gelation Time (sec.) 90 120 90 120 Thickness (mm) 1.22 1.07
1.20 1.11 Expansion ratio (%) 160 140 160 150 Density (g/cm.sup.3)
0.90 1.03 0.92 1.00
Example 54
D50, Size Span, TGA and DSC Analysis
[0543] A thermogravimetric analysis (TGA; 35 to 250.degree.
C./10.degree. C./min) and a differential scanning calorimetry (DSC)
thermal analysis were performed on some samples of functionalized
particulate sodium bicarbonates and a non-functionalized sodium
bicarbonate (Ex. 53A). The results are provided in TABLE 28. The
D.sub.50 (.mu.m) and size span of these sodium bicarbonates, as
well as the lowest density (p) and highest expansion ratio (%) of
PVC foams with their corresponding gelation time at the
corresponding oven temperature obtained with these sodium
bicarbonates are provided in TABLE 28.
TABLE-US-00029 TABLE 28 PVC TGA/DSC Analysis Plastisol dTGA dTGA
DSC Particulate sodium testing TGA Temp Temp Start Max Max
bicarbonate Gel .rho.**/ Total 15% 95% Loss Loss peak Size temp/
exp loss Loss Loss Temp Temp Temp EX Additive * D.sub.50 Span time
ratio (%) (.degree. C.) (.degree. C.) (.degree. C.) (.degree. C.)
(.degree. C.) 15A 10 wt % EB 57 2.0 210/120 0.37/410 33.5 157.9
183.1 130.5 170.7 175.9 Carnauba wax 16A 25 wt % GB 29 5.3 210/120
0.42/340 32.2 136.7 195.7 126.3 172.6 178.1 GMS 18A 4 wt % EB 30
2.3 210/90 0.33/430 36.5 125.8 165.2 99.4 138.2 146.0 poly (meth)
acrylate 21A 20 wt % FB 29 3.0 200/120 0.42/360 34.8 127.6 185.7
96.6 144.2 151.6 arabic gum 34A 35 wt % EB 45 3.4 200/120 0.46/310
39.7 150.7 230.2 106.3 151.9 233.6 PVOH 37A 1 wt % B 19 2.8 210/90
0.43/370 36.6 155.9 173.4 120.4 158.9 164.3 Rosin acid 53A -- B 7
2.1 200/90 0.90/160 35.4 116.7 149.8 77.3 129.2 137.1 control *
Methods of functionalization: EB: Extrusion followed by milling;
GB: Spray agglomeration followed by milling; FB: fluid bed spray
coating following by milling; B: Milling **.rho. = Density of PVC
foam (g/cm.sup.3); Exp ratio = expansion ratio obtained at the gel
temperature/time
[0544] The TGA results show that both the CO.sub.2 release
beginning temperature and the CO.sub.2 release maximum temperature
increased in the functionalized sodium bicarbonate samples
comprising a functionalizing additive compared to a milled
commercial sodium bicarbonate product SOLVAY SB/03 (Ex. 53A) which
was not functionalized with an additive.
[0545] The DSC analysis showed that the peak temperature for the
functionalized sodium bicarbonate samples comprising a
functionalizing additive was higher than a milled commercial sodium
bicarbonate product SOLVAY SB/03 (Ex. 53A) which was not
functionalized with an additive.
[0546] The disclosure of all patent applications, and publications
cited herein are hereby incorporated by reference, to the extent
that they provide exemplary, procedural or other details
supplementary to those set forth herein.
[0547] Should the disclosure of any of the patents, patent
applications, and publications that are incorporated herein by
reference conflict with the present specification to the extent
that it might render a term unclear, the present specification
shall take precedence.
[0548] In the present application, where an element or component is
said to be included in and/or selected from a list of recited
elements or components, it should be understood that in related
embodiments explicitly contemplated here, the element or component
can also be any one of the individual recited elements or
components, or can also be selected from a group consisting of any
two or more of the explicitly listed elements or components. Any
element or component recited in a list of elements or components
may be omitted from such list. Further, it should be understood
that elements, embodiments, and/or features of processes or methods
described herein can be combined in a variety of ways without
departing from the scope and disclosure of the present teaching,
whether explicit or implicit herein.
[0549] Accordingly, the scope of protection is not limited by the
description set out above, but is only limited by the claims which
follow, that scope including all equivalents of the subject matter
of the claims. Each and every claim is incorporated into the
specification as an embodiment of the present invention. Thus, the
claims are a further description and are an addition to the
preferred embodiments of the present invention. While preferred
embodiments of this invention have been shown and described,
modifications thereof can be made by one skilled in the art without
departing from the spirit or teaching of this invention. The
embodiments described herein are exemplary only and are not
limiting. Many variations and modifications of systems and methods
are possible and are within the scope of the invention.
* * * * *