U.S. patent application number 10/775518 was filed with the patent office on 2004-08-19 for shelf stable haze free liquids of overbased alkaline earth metal salts, processes and stabilizing halogen-containing polymers therewith.
Invention is credited to Dominey, Lawrence A., Ramey, Chester E., Reddy, James E..
Application Number | 20040162372 10/775518 |
Document ID | / |
Family ID | 25335676 |
Filed Date | 2004-08-19 |
United States Patent
Application |
20040162372 |
Kind Code |
A1 |
Reddy, James E. ; et
al. |
August 19, 2004 |
Shelf stable haze free liquids of overbased alkaline earth metal
salts, processes and stabilizing halogen-containing polymers
therewith
Abstract
Shelf stable haze free liquids of overbased alkaline earth metal
salts are obtained by reacting metal base with fatty acids in the
presence of liquid hydrocarbon and aliphatic alcohols having at
least 8 carbon atoms to provide overbased liquids essentially free
of a phenol or a phenolic derivative. Stabilizer compositions
containing the overbased liquids and mixed metal stabilizers of
zinc, cadmium and tin are provided for stabilizing
halogen-containing polymers.
Inventors: |
Reddy, James E.; (Lyndhurst,
OH) ; Ramey, Chester E.; (Chagrin Falls, OH) ;
Dominey, Lawrence A.; (Chagrin Falls, OH) |
Correspondence
Address: |
WOOD, HERRON & EVANS, L.L.P.
2700 Carew Tower
441 Vine St.
Cincinnati
OH
45202
US
|
Family ID: |
25335676 |
Appl. No.: |
10/775518 |
Filed: |
February 10, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10775518 |
Feb 10, 2004 |
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09861393 |
May 18, 2001 |
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6689893 |
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Current U.S.
Class: |
524/379 ;
524/394; 524/418 |
Current CPC
Class: |
C07C 51/414 20130101;
C10N 2070/00 20130101; C07C 51/412 20130101; C10M 2207/26 20130101;
C10N 2010/04 20130101; C10N 2030/04 20130101; C07C 57/12 20130101;
C08K 3/24 20130101; C08K 5/0091 20130101; C10N 2030/06 20130101;
C08K 5/098 20130101; C07C 51/412 20130101; C07C 57/12 20130101;
C07C 51/414 20130101; C07C 57/12 20130101; C08K 5/0091 20130101;
C08L 57/08 20130101 |
Class at
Publication: |
524/379 ;
524/394; 524/418 |
International
Class: |
C08K 005/05; C08K
005/09; C08K 003/30 |
Claims
What is claimed is:
1. A shelf stable haze free liquid of an overbased alkaline earth
metal salt of a fatty acid comprising an alkaline earth metal salt
from the group consisting of carbonate, sulfate, sulfide and
sulfite, an alkaline earth metal carboxylate of a fatty acid, a
liquid hydrocarbon, and an aliphatic alcohol having at least 8
carbon atoms, said liquid being essentially free of a phenol or
phenolic derivative.
2. The shelf stable haze free liquid of claim 1 wherein said fatty
acid is a C.sub.12-C.sub.22 fatty acid.
3. The shelf stable haze free liquid of claim 1 wherein said fatty
acid is oleic acid.
4. The shelf stable haze free liquid of claim 1 wherein said
alkaline earth metal is selected from the group consisting of
calcium, barium, magnesium and strontium.
5. The shelf stable haze free liquid of claim 1 wherein said
alkaline earth metal is calcium.
6. The shelf stable haze free liquid of claim 1 wherein the
overbased alkaline earth salt is calcium oleate/carbonate.
7. The shelf stable haze free liquid of claim 1 which is a
microemulsion having micells of the alkaline earth metal carbonate
and an alkaline earth metal carboxylate of a fatty acid, and a
continuous phase of the liquid hydrocarbon and the aliphatic
alcohol.
8. The shelf stable haze free liquid of claim 1 wherein the alcohol
has 8 to 14 carbon atoms.
9. The shelf stable haze free liquid of claim 1 wherein said
alcohol is selected from the group of isodecanol, dodecanol,
octanol, tridecanol and tetradecanol, and mixtures thereof.
10. The shelf stable haze free liquid of claim 9 which further
contains a glycol or a glycol ether.
11. The shelf stable haze free liquid of claim 10 wherein the
glycol or glycol ether is selected from the group consisting of
diethylene glycol monobutyl ether, triethylene glycol, dipropylene
glycol, diethylene glycol monomethyl ether, ethylene glycol
monobutyl ether, and mixtures thereof.
12. The shelf stable haze free liquid of claim 1 containing about
4% up to about 36% by weight of alkaline earth metal.
13. The shelf stable haze free liquid of claim 12 wherein the
alkaline earth metal is calcium which is contained in an amount of
about 9% to about 15% by weight.
14. A shelf stable haze free liquid of an overbased calcium salt of
a fatty acid comprising calcium carbonate, calcium carboxylate of a
fatty acid, a liquid hydrocarbon, and an aliphatic alcohol having
at least 8 carbon atoms.
15. The shelf stable haze free liquid of claim 14 which is
essentially free of a phenol or phenolic derivative.
16. The shelf stable haze free liquid of claim 14 wherein the
liquid hydrocarbon is an oil.
17. The shelf stable haze free liquid of claim 14 wherein the
liquid hydrocarbon is selected from the group consisting of an oil,
mineral spirits and non-aromatic hydrocarbons.
18. The shelf stable haze free liquid of claim 14 wherein said
fatty acid is a C.sub.12-C.sub.22 fatty acid.
19. The shelf stable haze free liquid of claim 14 wherein said
fatty acid is oleic acid.
20. The shelf stable haze free liquid of claim 14 which is a
microemulsion having micells of the alkaline earth metal carbonate,
and an alkaline earth metal carboxylate of a fatty acid, and a
continuous phase of the liquid hydrocarbon and the aliphatic
alcohol.
21. The shelf stable haze free liquid of claim 14 wherein said
alcohol is isodecanol.
22. The shelf stable haze free liquid of claim 20 wherein the
continuous phase further contains a glycol or a glycol ether.
23. The shelf stable haze free liquid of claim 22 wherein the
glycol or glycol ether is selected from the group consisting of
diethylene glycol monobutyl ether, triethylene glycol, dipropylene
glycol, diethylene glycol monomethyl ether, ethylene glycol
monobutyl ether, and mixtures thereof.
24. The shelf stable haze free liquid of claim 14 containing about
4% up to about 36% by weight calcium.
25. The shelf stable shelf stable haze free liquid of claim 14
wherein calcium is contained in an amount of at least about 9% to
about 15% by weight.
26. A process for preparing a shelf stable haze free liquid of an
overbased alkaline earth metal salt of a fatty acid comprising
reacting an alkaline earth metal base and a fatty acid with an
equivalent ratio of metal base to fatty acid being greater than 1:1
in the presence of liquid hydrocarbon, carbonating the mixture to
produce amorphous alkaline earth metal carbonate, adding during
carbonation a dispersion of alkaline earth metal base, a liquid
hydrocarbon and an aliphatic alcohol having at least 8 carbon atoms
in relative amounts at a controlled rate of alkaline earth metal
base addition to produce a stable haze free liquid reaction
product, and removing water from the reaction product to obtain a
shelf stable haze free liquid overbased alkaline earth metal
salt.
27. The process of claim 26 further comprising filtering the liquid
reaction product to produce a thermodynamically stable liquid at a
product filtration rate of at least about 300 ml per 10
minutes.
28. The process of claim 26 wherein said fatty acid is a
C.sub.12-C.sub.22 fatty acid.
29. The process of claim 26 wherein said fatty acid is oleic
acid.
30. The process of claim 26 wherein water is removed to provide a
microemulsion product having less than about 1% by weight water of
the total product.
31. The process of claim 26 wherein said alkaline earth metal is
selected from the group consisting of calcium, barium, magnesium
and strontium.
32. The process of claim 26 wherein said alkaline earth metal is
calcium.
33. The process of claim 26 wherein the overbased salt is calcium
oleate/carbonate.
34. The process of claim 26 to produce the overbased salt which is
essentially free of a phenol or phenolic derivative.
35. The process of claim 26 wherein said aliphatic alcohol has 8 to
14 carbon atoms.
36. The process of claim 35 wherein the alcohol is isodecanol.
37. The process of claim 36 wherein the continuous phase further
contains a glycol or a glycol ether.
38. The process of claim 37 wherein the glycol or glycol ether is
selected from the group consisting of diethylene glycol monobutyl
ether, triethylene glycol, dipropylene glycol, diethylene glycol
monomethyl ether, ethylene glycol monobutyl ether, and mixtures
thereof.
39. The process of claim 26 by reacting on the basis of the final
reaction mixture an amount of an alkaline earth metal base selected
from the group consisting of about 15-30% calcium hydroxide, about
12-24% magnesium hydroxide, about 25-50% strontium hydroxide, and
about 35-50% barium hydroxide, and mixtures thereof.
40. The process of claim 39 wherein the alkaline earth metal base
is calcium hydroxide and the fatty acid is oleic acid.
41. The process for preparing a shelf stable haze free liquid of an
overbased calcium oleate/carbonate comprising reacting calcium
hydroxide base and oleic acid with an equivalent ratio of the base
to the acid being greater than 1:1 in the presence of a mixture of
liquid hydrocarbon and catalyst, carbonating the mixture to produce
amorphous calcium carbonate, adding during carbonation a dispersion
of calcium hydroxide, liquid hydrocarbon and cosurfactant aliphatic
alcohol having at least 8 carbon atoms in relative amounts at a
controlled rate of calcium hydroxide addition to produce a stable
haze free liquid reaction product, and removing water from the
reaction product to provide a shelf stable haze free overbased
calcium oleate/carbonate.
42. The process of claim 41 comprising the further step of
filtering the liquid reaction product to remove byproducts or
impurities.
43. The process of claim 41 which is conducted essentially free of
a phenol or a phenolic derivative.
44. The process of claim 41 wherein the catalyst is selected from
the group consisting of propionic acid, citric acid, acetic acid
and adipic acid.
45. The process of claim 41 wherein the surfactant is calcium
oleate borne by the reaction of the base and the oleic acid in
situ.
46. The process of claim 41 wherein the cosurfactant is an
aliphatic alcohol having 8 to 14 carbon atoms.
47. The process of claim 46 wherein the alcohol selected is
isodecanol in the presence of diethylene glycol monobutyl ether and
triethylene glycol.
48. The process of claim 46 wherein the haze free liquid calcium
oleate is a microemulsion having amorphous calcium carbonate within
the micelles of the microemulsion.
49. The process of claim 41 wherein after the addition of the
dispersion and carbonation with carbon dioxide the mixture contains
about 15-30% calcium oleate, about 9-35% calcium carbonate, about
30-35% hydrocarbon oil, about 15-18% idodecanol, and about 4-6%
glycol or glycol ether.
50. The process of claim 49 wherein the dispersion contains about
40-50% calcium hydroxide, about 25-40% hydrocarbon oil, about
10-25% isodecanol and about 0-10% glycol or glycol ether.
51. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 1.
52. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 2.
53. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 3.
54. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 4.
55. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 5.
56. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 6.
57. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 8.
58. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 10.
59. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 11.
60. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 12.
61. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 13.
62. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 15.
63. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 16.
64. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 17.
65. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 18.
66. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 24.
67. A halogen-containing polymer composition comprising a
halogen-containing polymer and a heat stabilizing amount of the
liquid of claim 25.
68. A mixed metal stabilizer composition for a halogen-containing
polymer comprising a metal compound stabilizer selected from the
group consisting of compounds of antimony, barium, calcium,
cadmium, zinc, lead, strontium, bismuth and tin, and mixtures
thereof, and a shelf stable haze free liquid of claim 1, 2, 3, 4,
5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18, 24, and 25, said metal
compound stabilizer and liquid in relative amounts for stabilizing
said polymers.
69. A mixed metal stabilizer composition for a halogen-containing
polymer comprising a metal compound stabilizer and a shelf stable
haze free liquid of calcium oleate/carbonate, said stabilizer and
liquid in relative amounts for stabilizing said polymer.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a shelf stable haze free
liquid of an alkaline earth metal salt of a fatty acid and a
process of producing the liquids. Mixed metal stabilizers
containing the overbased liquids and metal carboxylates of zinc,
cadmium or alkyltin are provided and used as stabilizers for
halogen-containing polymers such as polyvinyl chloride (PVC).
BACKGROUND OF THE INVENTION
[0002] The preparation of overbased calcium or barium salts of
carboxylic acids, alkyl phenols, and sulfonic acids are disclosed
in the following U.S. Pat. Nos.: 2,616,904; 2,760,970; 2,767,164;
2,798,852; 2,802,816; 3,027,325; 3,031,284; 3,342,733; 3,533,975;
3,773,664; and 3,779,922. The use of these overbased metal salts in
the halogen-containing organic polymer is described in the
following U.S. Pat. Nos.: 4,159,973; 4,252,698; and 3,194,823. The
use of overbased barium salt in stabilizer formulations has
increased during recent years. This is due, in the main, to the
fact that overbased barium salts possess performance advantages
over the neutral barium salts. The performance advantages
associated with overbased barium salts are low plate-out, excellent
color hold, good long-term heat stability performance, good
compatibility with the stabilizer components, etc. Unfortunately,
most of the overbased barium salts are dark in color and, while
these dark colored overbased barium salts are effective stabilizers
for halogen-containing organic polymer, their dark color results in
the discoloration of the end product. This feature essentially
prohibits the use of dark colored overbased barium salts in
applications where a light colored polymer product is desired.
[0003] According to the teachings of U.S. Pat. No. 4,665,117, light
colored alkali or alkaline earth metal salts are prepared where
alkyl phenol is used as a promoter. However, alkyl phenol is also a
major cause for the development of color in the final product. This
problem is overcome by the use of propylene oxide which displaces
the hydrogen of the phenolic hydroxyl group and thereby restricts
the formation of colored species. However, there are disadvantages
associated with this approach, principally due to the toxic nature
of propylene oxide. Propylene oxide is classified as a possible
carcinogen and laboratory animal inhalation studies have shown
evidence of a link to cancer. Propylene oxide is also listed as a
severe eye irritant, and prolonged exposure to propylene oxide
vapors may result in permanent damage to the eye. Furthermore,
propylene oxide is extremely flammable and explosive in nature
under certain conditions. Propylene oxide boils at 94.degree. F.
and flashes at -20.degree. F. As a result, extreme precautions are
required to handle propylene oxide at the plant site. Special
storage equipment is required for propylene oxide and other safety
features are necessary. U.S. Pat. No. 4,665,117 describes the use
of propylene oxide at 150.degree. C. At this temperature, propylene
oxide will be in the gaseous phase. Under these operating
conditions, more than stoichiometric amounts of propylene oxide are
required to carry the reaction to completion because propylene
oxide will escape from the reaction mixture and this requires
additional handling of the excess propylene oxide.
[0004] With the movement in the plastics industry to remove heavy
metals, liquid calcium-zinc stabilizers are desirous, but not
practical, as replacements for barium-cadmium or barium-zinc. Low
metal concentrations, poor compatibility, haziness in clear
products and plate out during processing in PVC have severely
limited the universal acceptance of calcium based liquid stabilizer
compositions. Problems are encountered in the stability of these
compositions upon standing or storage. Storage stability is due to
the incompatibility among the metal salts employed in the
composition and is exhibited by increased turbidity, viscosity, or
insoluble solids over time. As a result, the liquid calcium
compositions are no longer homogeneous or readily pourable and must
be specially treated in order to be used. U.S. Pat. No. 5,322,872
is directed to stabilized compositions of mixed metal carboxylates
having improved storage stability. According to this patent, a
complexing agent is added to the mixed metal carboxylate in order
to improve shelf stability. Complexing agents disclosed in this
patent include phosphines, phosphites, aromatic cyanides, aromatic
hydroxy compounds, oximes and other compounds. U.S. Pat. Nos.
5,830,935 and 5,859,267 have also issued as directed to processes
for improving basic metal salts and stabilizing halogen-containing
polymers therewith.
[0005] Notwithstanding the state of the art as exemplified by the
above patents, there is a need for further improvements in making
shelf stable compositions of overbased alkaline earth metal
carboxylates and in methods for their use in stabilizing
halogen-containing polymers.
SUMMARY
[0006] The present invention relates to a shelf stable haze free
liquid of an overbased alkaline earth metal salt of a fatty acid.
In a preferred form, these liquids contain an alkaline earth metal
carbonate, an alkaline earth metal carboxylate of a fatty acid, a
liquid hydrocarbon, and an aliphatic alcohol having at least 8
carbon atoms. These liquids are referred to sometimes hereinafter
more simply as "overbased alkaline earth metal salt(s)" or
"overbased alkaline earth metal carboxylate(s)/carbonate(s)".
Liquid overbased calcium and barium salts are preferably provided
and, in a preferred form of the invention, the liquids are
essentially free of a phenol or a phenolic derivative.
[0007] The invention also relates to a process for preparing the
shelf stable haze free liquid of an overbased alkaline earth metal
salt of a fatty acid. The process involves reacting an alkaline
earth metal base and a fatty acid with an equivalent ratio of metal
base to fatty acid being greater than 1:1 in the presence of a
liquid hydrocarbon. A surfactant and catalyst are used to promote
the reaction. The mixture is acidified, preferably by carbonation,
to produce an amorphous alkaline earth metal carbonate. During
carbonation, a dispersion of alkaline earth metal base, a liquid
hydrocarbon, and an aliphatic alcohol having at least 8 carbon
atoms, is added in relative amounts to produce a stable haze free
liquid reaction product. Water is removed from the reaction product
to obtain a shelf stable haze free liquid overbased alkaline earth
metal salt.
[0008] It has been found important during carbonation to add the
dispersion of metal base, liquid hydrocarbon and aliphatic alcohol
in relative amounts at a controlled rate to produce the stable haze
free reaction product. There are a number of reasons which are
believed to contribute to the formation of a stable haze free
liquid which is then filterable to remove impurities and byproducts
of the reaction. Up to the discoveries made in accordance with the
principles of this invention, it was not considered possible to
make in a practical or commercial operation an overbased calcium
fatty acid salt, for example, that may be filtered at commercial or
practical rates to remove unwanted impurities and byproducts of the
reaction to produce a shelf stable haze free liquid. In contrast,
it has been found that by the continuous addition of the dispersion
or slurry of base during carbonation, such results are achievable.
It is believed that the metal base slurry prevents the formation of
undesirable calcium carbonate crystals or byproducts in the desired
overbased metal salt. These undesirable moieties prevent the
formation of stable haze free products which are filterable. In
other words, the metal base slurry is added at a controlled rate
which does not exceed the rate of the desired product-forming
reaction. The reaction is controlled by continuous or incremental
addition of the metal base to make the calcium ions immediately
available for the desired reaction as opposed to allowing the metal
base, for example lime, to react and form a byproduct. Excessive
byproduct or lime coated with calcium carbonate is believed to
render the liquid product unfilterable. Using this procedure, the
pH is controlled during the reaction so that the fatty acid is
neutralized and the pH rises to about 10-12 with the continued
addition of base to produce dissolved metal ion which reacts with
CO.sub.2 during carbonation to produce the desired product. It is
believed if the reaction rate is not controlled, and the base is
not dissolved, then solid base reacts or is coated with calcium
carbonate to form undesirable byproducts. The formation of
undesirable byproducts of the reaction renders the final product
unstable and unfilterable.
[0009] The haze free liquids of the overbased alkaline earth metal
fatty acid salts are suitable for use in making mixed metal
stabilizer compositions with zinc, cadmium or alkyltin
carboxylates. Other metal compound stabilizers that are well known
may be used where the metal component can also be barium, calcium,
strontium, lead, bismuth or antimony, and mixtures thereof. The
mixed metal stabilizer compositions provide heat and/or light
stability to vinyl halide resins such as polyvinyl chloride (PVC),
and the like.
[0010] A number of benefits are obtained by the products and
processes of this invention. Improvements in shelf stability of
liquid overbased alkaline earth metal fatty acid salts are
achieved. In particular, shelf stabilities are achieved with the
liquids being free of phenol and phenolic derivatives such as
phenolic reaction products. This is an especially desirable
advantage in view of the efforts of the trade to reduce or
eliminate such phenolic products because of environmental concerns.
Also, as developed above, such phenols are a source of color
development. In addition, enhanced shelf stability for the liquid
overbased calcium fatty acid carboxylates and mixed metal
stabilizer compositions of the invention have been demonstrated
over presently commercially available products. In particular,
presently available liquid overbased calcium fatty acid
carboxylates exhibit the development of turbidity or haze, whereas
the liquid compositions of this invention remain stable over
extended periods of time. Therefore, the haze free liquids of this
invention allow easy handling, storage and filtration. Furthermore,
when the mixed metal stabilizer systems containing liquid overbased
barium or calcium carboxylates are employed in vinyl halide
polymers, they exhibit better compatibilities with improvements in
thermal stability, clarity and plate out resistance.
[0011] The above advantages, benefits and further understanding of
this invention will be apparent with reference to the following
detailed description and preferred embodiments.
DETAILED DESCRIPTION AND PREFERRED EMBODIMENTS
A. Shelf Stable Haze Free Liquids of Overbased Alkaline Earth Metal
Salts
[0012] In one preferred form of the invention, the shelf stable
haze free liquid of an overbased alkaline earth metal salt of a
fatty acid comprises
[0013] an alkaline earth metal carbonate,
[0014] an alkaline earth metal carboxylate of a fatty acid,
[0015] a liquid hydrocarbon, and
[0016] an aliphatic alcohol having at least 8 carbon atoms, with
the liquid being preferably free of a phenol or a phenolic
derivative such as a phenolic reaction product.
[0017] In another form of the invention, the alkaline earth metal
sulfate, sulfide or sulfite may be formed instead of the carbonate
where the acidic gas used in the process is sulfur dioxide, sulfur
trioxide, carbon disulfide, or hydrogen sulfide.
[0018] The fatty acid of the overbased liquid carboxylate is
generally a C.sub.12-C.sub.22 fatty acid, including, for example,
lauric, myristic, palmitic, stearic, archidic and behenic, among
the saturated fatty acids. Unsaturated fatty acids include
palmitoleic, oleic, linoleic, and linolenic. Among these fatty
acids, oleic is presently preferred in preparing the overbased
liquid carboxylates.
[0019] The alkaline earth metal of the salt is selected from the
group consisting of calcium, barium, magnesium and strontium. For
example, shelf stable haze free overbased calcium oleates have been
prepared. These overbased calcium salts contain calcium carbonate,
calcium oleate, a liquid hydrocarbon diluent and an aliphatic
alcohol having at least 8 carbon atoms.
[0020] In a broad form of the invention, it is important to have an
aliphatic alcohol having at least 8 carbon atoms, more preferably
an alcohol having 8 to 14 carbon atoms, such as, isodecanol,
dodecanol, octanol, tridecanol and tetradecanol. Isodecanol is
presently preferred. It has been found that when a higher aliphatic
alcohol is employed in making the overbased product, phenol may be
excluded from the reaction as a promoter. This is a particularly
advantageous feature of the invention where it is undesirable to
have a phenol or phenolic reaction product involved in the
manufacture or use of the overbased liquid.
[0021] In another form of the invention, the liquid overbased
alkaline earth salt of the fatty acid is believed to be a
thermodynamically stable microemulsion. The microemulsion has
micells and a continuous phase. The micells consist of an alkaline
earth metal carbonate and an alkaline earth metal carboxylate of
the fatty acid. The continuous phase of the microemulsion consists
of the liquid hydrocarbon and the higher aliphatic alcohol.
[0022] Haze free liquids of the overbased metal salts have been
prepared containing at least 4% by weight or more of the alkaline
earth metal up to about 36% by weight. In the case of the overbased
calcium salts, up to about 13-15% by weight calcium are produced
and, for barium salts, up to about 36% by weight barium may be
produced. In the preparation of higher overbased products, for
example, containing about 13-15% by weight metal, it has been found
suitable to use a glycol or a glycol ether along with the higher
aliphatic alcohol. A glycol or glycol ether may be selected from
the group consisting of diethylene glycol monobutyl ether (butyl
Carbitol.RTM.), triethylene glycol, dipropylene glycol, diethylene
glycol monomethyl ether, ethylene glycol monobutyl ether, and
mixtures thereof.
B. The Basic Process and Critical Features
[0023] The process of the present invention for preparing a shelf
stable haze free liquid of an overbased alkaline earth metal salt
of a fatty acid comprises reacting an alkaline earth metal base and
a fatty acid with an equivalent ratio of metal base to the fatty
acid being greater than 1:1 in the presence of a mixture of liquid
hydrocarbon. A surfactant and catalyst promote the reaction. The
mixture is acidified and preferably carbonated to produce amorphous
alkaline earth metal carbonate. During carbonation, a dispersion is
added containing alkaline earth metal base, liquid hydrocarbon and
an aliphatic alcohol having at least 8 carbon atoms in relative
amounts at a controlled rate of base addition to produce a stable
haze free liquid reaction product. Water is removed from the
reaction product to produce a shelf stable haze free liquid
overbased alkaline earth metal salt. Generally, it is preferred
that the entire process be conducted in the absence of free oxygen
and, for this purpose, an atmosphere of nitrogen is used.
[0024] As developed above, one of the important features of the
method is the step of adding during carbonation a dispersion of
alkaline earth metal base, liquid hydrocarbon and an aliphatic
alcohol having at least 8 carbon atoms at a controlled rate of base
addition to produce the stable haze free liquid. It has been found
that the addition of a dispersion of the base in the liquid
hydrocarbon and aliphatic alcohol protects or passivates the base,
thereby enabling the formation of a stable haze free liquid
reaction product. By protecting or passivating the base,
carbonation proceeds to produce amorphous alkaline earth metal
carbonate. Unexpectedly, the reaction proceeds without the need to
remove water during the reaction and results in a very stable haze
free liquid reaction product. At the end of the reaction, water is
removed, preferably to the level of less than 1%, more preferably
less than 0.3% or 0.1%, in the obtainment of the shelf stable
liquid overbased salt. The removal of water which is added during
the reaction or formed by the reaction is necessitated because it
forms a separate phase which impedes either the product of the
reaction or the formation of a shelf stable haze free liquid.
[0025] Other features of the method include filtering the product
of the reaction to produce a shelf or thermodynamically stable
liquid at a product filtration rate of at least about 300 ml per 10
minutes. In a preferred form of the invention, the product which is
produced is filterable to remove unwanted byproducts and enhance
the shelf stability of the overbased liquid. For example, with a
Buchner funnel having a 15 cm diameter under vacuum of about 25-30
inches Hg with a Whatman No. 1 filter and a diatomaceous filtering
aid (Celite.RTM. 512-577), the product is filterable at
satisfactory rates. One of the important discoveries of the method
of this invention is the ability to filter the reaction product to
form a stable haze free liquid at filtration rates which heretofore
were unachievable. This was especially the case when higher levels
of metal content in the overbased liquids were desired, especially
overbased calcium liquids. Thus, filtration removes undesirable
impurities including silica, iron oxide and other metal species,
unreacted calcium hydroxide, calcium carbonate, and other oxides
which may contribute to lack of stability. These byproducts or
impurities may comprise up to about 6% of byproduct of the
reaction.
[0026] Throughout this specification and claims, the term "basic"
or "overbased" as applied to the alkaline earth metal salts is used
to refer to metal compositions wherein the ratio of total metal
contained therein to the fatty acid moieties is greater than the
stoichiometric ratio of the neutral metal salt. That is, the number
of metal equivalents is greater than the number of equivalents of
the fatty acid. In some instances, the degree to which excess metal
is found in the basic metal salt is described in terms of a "metal
ratio". Metal ratio as used herein indicates the ratio of total
alkaline earth metal in the oil-soluble composition to the number
of equivalents of the fatty acid or organic moiety. The basic metal
salts often have been referred to in the art as "overbased" or
"superbased" to indicate the presence of an excess of the basic
component.
[0027] The process of the present invention may be used to prepare
shelf stable liquids of the alkaline earth metal carboxylates of
the fatty acids. As stated above, the method may be practiced
without the use of phenol promoter or phenolic reaction product.
Therefore, liquid overbased barium fatty acid carboxylates have
been made without the need for a phenol or phenolic reaction
product in order to achieve a shelf stable haze free liquid. In the
case of liquid overbased calcium fatty acid carboxylates, shelf
stable haze free products are obtained without a phenol where the
aliphatic alcohol having at least 8 carbon atoms is employed.
[0028] The alkaline earth metal bases utilized as a reaction
component may be derived from any alkaline earth metals and, of
these, calcium and barium bases are particularly preferred. The
metal bases include metal oxides and hydroxides and, in some
instances, the sulfides, hydro sulfides, etc. While a phenolic
component or reactant may preferably be excluded from a reaction,
in the case of liquid overbased calcium products, the phenol or
alkyl phenol may be included to yield liquid overbased products. As
stated above, the fatty acids, or mixtures thereof, as identified
above may be used in the reaction mixture. For example, a
surfactant that facilitates the reaction is the alkaline earth
metal carboxylate of the fatty acid that is formed in situ. Other
surfactants may be included, for example, general purpose surface
active agents identified under the trademark Tween which are
polyoxyethylene derivatives of fatty acid partial esters of
sorbitol anhydrides, particularly mono- and di-oleates of the
ethoxylated sorbitol, and polyisobutyle succinic acid. Furthermore,
it is desirable to include a catalyst to facilitate the speed of
the reaction such as propionic acid, citric acid, acetic acid and
adipic acid. The hydrocarbon liquid employed in the process and the
liquid reaction products generally includes any hydrocarbon
diluent. Most generally, the liquid hydrocarbon is selected from
the group of an oil, mineral spirits and non-aromatic
hydrocarbons.
C. Amounts of Reactants and Catalysts
[0029] The amount of alkaline earth metal base utilized in the
preparation of basic salts is an amount which is more than one
equivalent of the base per equivalent of fatty acid or organic
moiety, and more generally, will be an amount sufficient to provide
at least three equivalents of the metal base per equivalent of the
acid. Larger amounts can be utilized to form more basic compounds,
and the amount of metal base included may be any amount up to that
amount which is no longer effective to increase the proportion of
metal in the product. When preparing the mixture, the amount of
fatty acid and the alcohol included in the mixture is not critical
except that the ratio of equivalents of the metal base of the
combination of the other components in the mixture should be
greater than 1:1 in order to provide a basic product. More
generally, the ratio of equivalents will be at least 3:1. In those
instances where phenol may be present in making an overbased
calcium, the ratio of equivalents of monocarboxylic acid to phenol
should be at least about 1.1:1; that is, the monocarboxylic acid is
present in excess with respect to the phenol.
[0030] The ranges of hydrocarbon oil, aliphatic alcohol (preferably
isodecanol), butyl Carbitol and triethylene glycol have been
selected such that, in the presence of the alkaline earth fatty
acid salt (i.e. Ca oleate) which acts as a primary surfactant, the
mixture forms a stable inverse microemulsion of the metal
carbonate, water, and surfactant (internal phase) and surfactant,
cosurfactant, and hydrocarbon (external continuous phase).
[0031] The acceptable ratios of hydrocarbon oil to cosurfactant
aliphatic alcohol (isodecanol) are about 2:1 to about 4:1, with
about 2:1 preferred. The glycol ethers may be used at about 1-15%
of the final product, butyl Carbitol preferably at about 6%, and
triethylene glycol at about 0-2%, preferably at about 0.6%.
[0032] The lime slurry which is added to the oleic acid in the
reaction is formulated to be an easily pumpable mixture with the
general composition of about 40-50% lime, about 25-40% hydrocarbon
oil, about 10-25% isodecanol, and about 0-10% butyl Carbitol. The
butyl Carbitol amount that is needed to make a pumpable slurry
increases as the % lime in the slurry increases.
[0033] The reaction mixture for an overbased calcium oleate, after
addition of the slurry and carbonation with carbon dioxide,
preferably has the following composition ranges:
1 Ca oleate (surfactant) about 15-30% Ca carbonate about 9-35%
Hydrocarbon oil about 30-35% Isodecanol (cosurfactant) about 15-18%
Butyl Carbitol about 4-6% Triethyleneglycol about 0-0.8%
[0034] The catalyst, propionic acid or a lower aliphatic mono, di,
or tricarboxylic acid is used in the amount of about 0-0.1% of the
final reaction mixture.
[0035] Substitution of magnesium, strontium, or barium for calcium
in the overbased salt is done on an equivalent basis of the metal
hydroxide. On the basis of the final reaction mixture, the
following amounts may be used:
2 Ca(OH).sub.2 (lime) about 15-30% Mg(OH).sub.2 about 12-24%
Sr(OH).sub.2 about 25-50% Ba(OH).sub.2 about 35-50%
[0036] The step of carbonation involves treating the mixtures
described above with an acidic gas in the absence of free oxygen
until the titratable basicity is determined using phenolphthalein.
Generally, the titratable basicity is reduced to a base number
below about 10. The mixing and carbonation steps of the present
invention require no unusual operating conditions other than
preferably the exclusion of free oxygen. The base, fatty acid and
liquid hydrocarbon are mixed, generally heated, and then treated
with carbon dioxide as the acidic gas, and the mixture may be
heated to a temperature which is sufficient to drive off some of
the water contained in the mixture. The treatment of the mixture
with the carbon dioxide preferably is conducted at elevated
temperatures, and the range of temperatures used for this step may
be any temperature above ambient temperature up to about
200.degree. C., and more preferably from a temperature of about
75.degree. C. to about 200.degree. C. Higher temperatures may be
used such as 250.degree. C., but there is no apparent advantage in
the use of such higher temperatures. Ordinarily, a temperature of
about 80.degree. C. to 150.degree. C. is satisfactory.
[0037] By the term "acidic gas" as used in this specification and
in the claims is meant a gas which upon reaction with water will
produce an acid. Thus, such gases as sulfur dioxide, sulfur
trioxide, carbon dioxide, carbon disulfide, hydrogen sulfide, etc.,
are exemplary of the acidic gases which are useful in the process
of this invention. Of these acids, sulfur dioxide and carbon
dioxide are preferred, and the most preferred is carbon dioxide.
When carbon dioxide is used the alkaline earth carbonate is formed.
When the sulfur gases are used, the sulfate, sulfide and sulfite
salts are formed.
D. Halogen-Containing Polymer
[0038] A halogen-containing polymer, such as a vinyl halide resin,
most commonly stabilized with the basic metal salts of this
invention is polyvinyl chloride. It is to be understood, however,
that this invention is not limited to a particular vinyl halide
resin such as polyvinyl chloride or its copolymers. Other
halogen-containing resins which are employed and which illustrate
the principles of this invention include chlorinated polyethylene,
chlorosulfonated polyethylene, chlorinated polyvinyl chloride, and
other vinyl halide resin types. Vinyl halide resin, as understood
herein, and as appreciated in the art, is a common term and is
adopted to define those resins or polymers usually derived by
polymerization or copolymerization of vinyl monomers including
vinyl chloride with or without other comonomers such as ethylene,
propylene, vinyl acetate, vinyl ethers, vinylidene chloride,
methacrylate, acrylates, styrene, etc. A simple case is the
conversion of vinyl chloride H.sub.2C=CHCl to polyvinyl chloride
(CH.sub.2CHCl--).sub.n wherein the halogen is bonded to the carbon
atoms of the carbon chain of the polymer. Other examples of such
vinyl halide resins would include vinylidene chloride polymers,
vinyl chloride-vinyl ester copolymers, vinyl chloride-vinyl ether
copolymers, vinyl chloride-vinylidene copolymers, vinyl
chloride-propylene copolymers, chlorinated polyethylene, and the
like. Of course, the vinyl halide commonly used in the industry is
the chloride, although others such as bromide and fluoride may be
used. Examples of the latter polymers include polyvinyl bromide,
polyvinyl fluoride, and copolymers thereof.
[0039] Metal compound heat stabilizers of vinyl halide resin
compositions are well known. These metal compounds serve to capture
HCl liberated during heat processing of the vinyl halide resin
composition into its final shape. The metal can be lead, cadmium,
barium, calcium, zinc, strontium, bismuth, tin, or antimony, for
example. The stabilizers are usually metal salts of a carboxylic
acid, advantageously of a C.sub.8-C.sub.24 carbon chain link
monocarboxylic acid such as lauric, oleic, stearic, octoic, or
similar fatty acid salts. Metal salts of alkyl phenates may be
used. Mixed metal salts of such acids, and their preparation, are
familiar to those skilled in the art to which this present
invention pertains. Mixed metallic carboxylates involving
calcium/zinc or barium/zinc blends alone and in combination with
other stabilizers or additives such as beta-diketones, phosphite
salts and phenolic antioxidants have been used. The metal
stabilizer is a mixed metal salt of a carboxylic acid. Mixed metal
salts of such acids, and their preparation, are also familiar to
those skilled in the art to which this present invention
pertains.
E. End Uses for the Stabilzers
[0040] The liquid stabilizers or mixed metal stabilizers of this
invention may be used in a number of end products. Examples
include: wall covering, flooring (vinyl tile and inlay), medical
devices, dip coating, chair mat, banner film, pigment dispersion,
vinyl siding, piping, fuel additive, cosmetic, ceiling tile,
roofing film, wear layer, play balls or toys, teethers, fencing,
corrugated wall panels, dashboards, and shifter boots.
[0041] The following Examples illustrate the preparation of the
shelf stable haze free liquids of the overbased salts in accordance
with the method of the present invention, but these examples are
not considered to be limiting the scope of this invention. Unless
otherwise indicated in the following examples and elsewhere in the
specification and claims, all parts and percentages are by weight,
and all temperatures are in degrees fahrenheit.
EXAMPLE 1
10% Overbased Calcium Oleate/Carbonate
[0042] A phenol-free 10% overbased calcium oleate/carbonate was
prepared according to this Example. A mixture of 308.42 g of oleic
acid (1.100 moles), 213.15 g mineral oil, 154.14 g of isodecyl
alcohol, 63.08 g of butyl Carbitol, 8.70 g of triethylene glycol,
26.97 g of water and 0.87 g of propionic acid was heated to
190.degree. F., with stirring, under a nitrogen atmosphere. To the
stirred mixture there was continuously added a dispersion comprised
of 38.98 g mineral oil, 13.86 g isodecyl alcohol, 3.71 g butyl
Carbitol and 43.28 g of lime (0.5498 moles) for about 33 minutes to
produce a solution of calcium oleate in the mixture. The dispersion
was added at a rate of about 3 g per minute. At this point in the
reaction, the mixture tested basic with phenolphthalein (about
10-12 pH). Then, to the stirred mixture there was continuously
added, over a period of about 3 hours and 56 minutes, a dispersion
comprised of 276.25 g mineral oil, 98.23 g isodecyl alcohol, 26.31
g butyl Carbitol and 306.75 g lime (3.897 moles) while the mixture
was being treated with carbon dioxide at 1.5 SCFH at
195-200.degree. F. The dispersion was also added at a rate of about
3 g per minute. The basicity of the reaction was checked to
maintain the basicity during the reaction. When the reaction
mixture tested nearly neutral to phenolphthalein, the carbon
dioxide addition was discontinued. The reaction mixture was then
heated to 300.degree. F. and a total of 99.36 g of water was
removed via a Dean-Stark trap. The resulting product mixture was
stirred and 24.00 g of filter aid (diatomaceous earth) was added.
The product mixture was filtered with suction, as stated above in
the description, at about 300 ml per 10 minutes, yielding a clear,
amber, mobile liquid filtrate of overbased calcium oleate/carbonate
which remained clear upon cooling to room temperature. The filtrate
was analyzed to contain 10.4% Calcium by weight.
EXAMPLE 2
14% Overbased Calcium Oleate/Carbonate
[0043] A phenol-free overbased calcium oleate/carbonate containing
14% calcium by weight was made according to this Example. In a
3-liter resin kettle equipped with an overhead stirrer, two gas
inlet tubes, a thermocouple, heating mantle and Dean-Stark trap
with condenser, was added 1700 g of a 9.89% overbased calcium
oleate/carboxylate made by the method of the previous example and
42.5 g of deionized water. The mixture was heated with stirring
under a nitrogen atmosphere to a temperature of 195.degree. F., and
a slurry containing 385 g of hydrated lime (94% calcium hydroxide),
231 g of hydrocarbon oil, 96.25 g of isodecyl alcohol, and 57.75 g
of butyl Carbitol was added at a rate of 3.42 g per minute over a 3
hour 45 minute period. After 5 minutes of slurry addition, carbon
dioxide was added to the reaction at a rate of 1.2 standard cubic
feet per hour. During the carbonation, a temperature of
195-200.degree. F. was maintained and pH was monitored as in
Example 1.
[0044] After the slurry addition was finished, the carbon dioxide
addition was continued until the reaction mixture was neutral, as
shown by a colorless sample when tested with phenolphthalein. The
reaction mixture was then heated to 300.degree. F. and both the
water added and the water produced in the reaction was removed via
the Dean-Stark trap. To the dehydrated reaction product was added
75 g of diatomaceous earth and the product was filtered with
suction, as above in Example 1, yielding a clear, amber, mobile
liquid filtrate of overbased calcium oleate/carboxylate which
remained clear on cooling to room temperature. The filtrate was
analyzed to contain 14.5% calcium by weight.
Shelf Stable Haze Free Liquid Tests
[0045] Shelf Stability of the Phenol-Free Liquid Overbased Calcium
Carboxylate/Carbonate of Example 1
[0046] Shelf stability of the phenol-free liquid overbased calcium
carboxylate/carbonate of Example 1 (referred to hereinafter as New
Calcium) was measured using a turbidity meter over a period of 60
days in order to study its shelf stability properties. The Old
Calcium referred to hereinafter is a formerly commercially
available overbased calcium carboxylate containing 14% Ca
(Lubrizol's product LZ 2118, OMG Plastistab 2118).
[0047] The following Table I summarizes the results:
3TABLE I 1 Day 7 Days 10 Days 22 Days 60 Days Stabilizer containing
7.8 7.7 8.0 7.7 7.5 New Calcium Stabilizer containing >200
>200 >200 >200 >200 Old Calcium
[0048] Turbidity readings were measured in Jackson Turbidity Units
(JTU). The turbidity observation between 1-30 indicates that the
product is free from haze, and the observation above 30 to 200 JTU
indicates that the product is hazy in nature. If the turbidity
observation stays constant over a period of time, this means that
the product possesses good shelf stability. This means that the
product does not pick up any haze or undergo change in physical
appearance over a period of time.
[0049] The data of Table I shows that the New Calcium possessed
good shelf stability over a 60-day period, whereas the commercially
available Old Calcium is hazy in nature.
[0050] Shelf Stability of Mixed Metal Stabilizer of Phenol-Free
Overbased Calcium Carboxvlate/Carbonate and Zinc Carboxylate
(Calcium/Zinc Stabilizer)
[0051] Shelf stability of mixed metal calcium/zinc stabilizers
containing New Calcium (Example 1) and Old Calcium was also
monitored over a period of 24 days as shown in Table II. The
stabilizer formulation contained 5% Ca, 1.2% Zn (zinc octoate),
3.5% P (diphenyl isodecyl phosphite), 5% carboxylic acid (oleic
acid),3% anti-oxidant, 3% .beta.-diketone (dibenzoyl methane) and
diluent.
4TABLE II 1 Day 4 Days 7 Days 10 Days 24 Days Stabilizer containing
23.2 25.1 26.2 24.4 24.7 New Calcium Stabilizer containing >200
>200 >200 >200 >200 Old Calcium
[0052] The data illustrates that incorporation of New Calcium,
versus Old Calcium, makes the mixed metal stabilizer shelf stable
and haze free.
[0053] The above shelf stability tests were repeated by
incorporating the New Calcium into a second stabilizer formulation.
Shelf stability and clarity of a calcium/zinc stabilizer containing
New and Old Calcium was monitored over a 24-day period, and the
results are shown in Table III. Stabilizer formulation contained 5%
Ca, 1.2% Zn (zinc octoate), 3.4% P (diphenyl decyl phosphite) 6%
carboxylic acid (3% oleic acid/3% benzoic acid), 3% nonyl phenol as
an anti-oxidant, 2% .beta.-diketone (octyl benzoyl methane) and
diluent.
5TABLE III 1 Day 4 Days 7 Days 10 Days 24 Days Stabilizer
containing 25.1 26.3 28.1 26.5 26.8 New Calcium Stabilizer
containing >200 >200 >200 >200 >200 Old Calcium
[0054] Again, the data illustrates that the New Calcium produces a
shelf stable haze free mixed metal stabilizer versus the Old
Calcium.
[0055] Shelf Stability of Mixed Metal Stabilizer of Overbased
Calcium/Tin Carboxylate Stabilizers (Calcium/Tin Stabilizer)
[0056] Shelf stability of a calcium/tin stabilizer containing New
Calcium (Example 1) and Old Calcium was monitored over a period of
25 days as shown in Table IV. Stabilizer formulation contained 5%
Ca, 1.5% Sn (tin maleate), 3% P (diphenyl decyl phosphite), 5%
carboxylic acid (oleic acid), 2% anti-oxidant (bisphenol-A), 3%
.beta.-diketone (dibenzoyl methane) and diluent.
6TABLE IV 1 Day 4 Days 7 Days 11 Days 25 Days Stabilizer containing
52 54 58 61 62 New Calcium Stabilizer containing >200 >200
>200 >200 >200 Old Calcium
[0057] The data illustrates that the incorporation of New Calcium,
versus Old Calcium, makes the stabilizer shelf stable.
[0058] Performance Comparisons: Thermal Degradation of PVC
[0059] The New Calcium (Example 1) and Old Calcium were
incorporated into mixed metal stabilizer compositions for the
purpose of observing their relative rate of thermal degradation in
PVC. The stabilizer compositions are as follows:
7 Stabilizer formulation A B New Calcium 5.5% Ca -- Old Calcium
(2118) -- 5.5% Ca Zinc carboxylate 1.2% Zn 1.2% Zn Organic
Phosphite 3.0% P 3.0% P Carboxylic Acid 4.0% 4.0% Anti-oxidant 3.0%
3.0% Beta Diketone 3.0% 3.0% Diluent as needed as needed
[0060] The performances of these stabilizers A and B were observed
in a PVC formulation containing 100 parts of PVC resin (K value
66), 30 parts phthalate plasticizer, 3 parts of epoxidized soybean
oil and 2 parts of either stabilizer A or B.
[0061] Stabilized PVC compounds were then milled at 350-360.degree.
F. for 5 minutes at 25 mil thickness. The thermal stability was
carried out at 375.degree. F. over 56 minutes. Yellowness [+b
chromaticity of CIELAB color space (Commission Internationale de
l'Eclairage) developed in 1976] was measured with a Minolta
calorimeter. The yellowness values of the rate of thermal
degradation are shown in the following Table V.
[0062] The PVC formulation containing the stabilizer with the New
Calcium (A) develops color at a slower rate than the PVC
formulation using the stabilizer with the Old Calcium (B).
8TABLE V Time (minutes) New Calcium A Old Calcium B 7 9.68 10.11 14
10.52 10.68 21 11.76 11.54 28 15.25 14.89 35 18.39 19.59 42 38.57
47.77 49 46.69 56.92 56 60.11 69.33
[0063] Performance Comparisons: Clarity
[0064] The New Calcium (Example 1) and Old Calcium, along with a
calcium carboxylate (C.sub.8), were incorporated into mixed metal
stabilizer compositions for the purpose of observing their
influence on the clarity of the PVC application. The stabilizer
compositions are as follows:
9 Stabilizer Formulation A B C New Calcium 5.5% -- -- Old Calcium
-- 5.5% -- Calcium Carboxylate (C.sub.8) -- -- 5.5% Ca Zinc
carboxylate 1.2% Zn 1.2% Zn 1.2% Zn Organic Phosphite 3.4% P 3.4% P
3.4% P Carboxylic Acid 5.0% 5.0% 5.0% Anti-oxidant 3.0% 3.0% 3.0%
Beta Diketone 2.0% 2.0% 2.0% Diluent as needed as needed as
needed
[0065] The relative degree of clarity of the 0.25 inch pressed PVC
formulations containing either stabilizer A, B or C was observed
after 5 minutes of exposure to 350.degree. F. and 15,000 pounds
pressure. The PVC formulation comprised of 100 parts PVC resin (K
value 66), 30 parts phthalate plasticizer, 3 parts of epoxidized
soybean oil and 2 parts of either stabilizer A, B or C.
[0066] The pressed PVC samples were placed vertically near printed
material to determine the crispness of the print when looking
through the press. Stabilizer A and B gave comparable crispness.
However, both stabilizer A and B gave better clarity or crispness
than stabilizer C.
[0067] Performance Comparisons: Plate Out
[0068] The New Calcium (Example 1) and Old Calcium along with a
non-carbonated calcium carboxylate were incorporated into mixed
metal stabilizer compositions for the purpose of observing their
influence on the resistance to plate out of the stabilizer during
processing of the vinyl formulation. The stabilizer compositions
have been identified above as A, B and C with A containing the New
Calcium, B containing the Old Calcium and C containing the
non-carbonated calcium carboxylate.
[0069] Plate out is determined by introducing a red pigment into a
PVC formulation containing the stabilizer and allowing the pigment
to migrate from the formulation to the metal rolls of a two roll
mill at 340.degree. F. A white clean up compound is then placed
onto the rolls and the degree of plate out is determined by the
amount of red picked up by the clean up compound. The colorimeter
assigns a numerical value on the CIElab scale for the degree of
redness or plate out (+a).
10 Red pigmented formulation: Clean up compound 100 PVC resin 100
PVC resin 40 phthalate plasticizer 40 phthalate plasticizer 8
epoxidized soybean oil 8 epoxidized soybean oil 0.2 Stearic acid
0.2 Stearic acid 2 red 2B pigment 4 Titanium dioxide 1.5 stabilizer
3 lead phosphite
[0070] The red formulation is milled for 4 minutes undisturbed
after which the clean up compound is introduced and milled for
three minutes undisturbed.
[0071] Colorimeter readings, +a value indicating increasing degree
of red:
11 Sample a-value A -2.28 B -2.07 C +24.3
[0072] There is essentially no difference between the New and Old
Calcium as far as plate out resistance. However, there is a
significant difference between A and C where the New Calcium
provides superior plate out resistance.
[0073] The above description provides a disclosure of particular
embodiments of the invention and is not intended for the purpose of
limiting the same thereto. As such, the invention is not limited to
only the above described embodiments, rather, it is recognized that
one skilled in the art would understand alternative embodiments in
view of the above description that fall within the scope of the
invention.
* * * * *