U.S. patent application number 10/960617 was filed with the patent office on 2006-04-13 for water repellant fiberglass binder comprising a fluorinated polymer.
Invention is credited to Philip Francis Miele.
Application Number | 20060078719 10/960617 |
Document ID | / |
Family ID | 36145713 |
Filed Date | 2006-04-13 |
United States Patent
Application |
20060078719 |
Kind Code |
A1 |
Miele; Philip Francis |
April 13, 2006 |
Water repellant fiberglass binder comprising a fluorinated
polymer
Abstract
Provided is a fiberglass binder composition which comprises a
polycarboxy polymer, a polyol and a fluorinated polymer. The binder
also preferably includes a catalyst which is an alkali metal salt
of a phosphorus-containing organic acid. The resultant binder
provides minimal processing difficulties and a fiberglass product
which exhibits minimal water absorption.
Inventors: |
Miele; Philip Francis;
(Highlands Ranch, CO) |
Correspondence
Address: |
Robert D. Touslee;Johns Manville
10100 West Ute Avenue
Littleton
CO
80127
US
|
Family ID: |
36145713 |
Appl. No.: |
10/960617 |
Filed: |
October 7, 2004 |
Current U.S.
Class: |
428/292.1 |
Current CPC
Class: |
D04H 1/587 20130101;
C08K 7/14 20130101; C08L 27/00 20130101; C08L 33/16 20130101; C08L
33/02 20130101; C08L 2666/04 20130101; C08L 2666/04 20130101; C08K
5/17 20130101; C08L 27/00 20130101; C08L 2666/04 20130101; Y10T
428/249924 20150401; C08L 33/06 20130101; C03C 25/26 20130101; C08L
33/06 20130101; D04H 1/64 20130101; C08L 33/02 20130101 |
Class at
Publication: |
428/292.1 |
International
Class: |
D04H 3/00 20060101
D04H003/00 |
Claims
1. A fiberglass binder, comprising an aqueous solution of a
polycarboxy polymer, a polyol and a fluorinated polymer.
2. The fiberglass binder of claim 1, wherein the molecular weight
of the polycarboxy polymer is less than 5000.
3. The fiberglass binder of claim 1, wherein the molecular weight
of the polycarboxy polymer is less than 3000.
4. The fiberglass binder of claim 1, wherein the binder further
comprises a catalyst which comprises an alkali metal salt of a
phosphorus-containing organic acid.
5. The fiberglass binder of claim 4, wherein the catalyst is sodium
hydophosphite, sodium phosphite, or a mixture thereof.
6. The fiberglass binder of claim 1, wherein the polyol is
triethanolamine.
7. The fiberglass binder of claim 1, wherein the polycarboxy
polymer comprises homopolymers and/or copolymers of polyacrylic
acid.
8. The fiberglass binder of claim 1, wherein the amount of
polycarboxy polymer and polyol in the binder is such that the ratio
of carboxy group equivalents to hydroxyl group equivalents is in
the range of from about 1/0.65 to 1/0.75.
9. The fiberglass binder of claim 1, wherein the fluorinated
polymer is a fluorinated acrylate copolymer.
10. A fiberglass binder, comprising an aqueous solution of a
homopolymer and/or copolymer of polyacrylic acid, where the
polyacrylic acid polymer has a molecular weight of 5000 or less,
triethanolamine and a fluorinated polymer.
11. The fiberglass binder of claim 10, wherein the binder further
contains a catalyst which comprises an alkali metal salt of a
phosphorus-containing organic acid.
12. The fiberglass binder of claim 10, wherein the amount of
polyacrylic acid polymer and triethanolamine in the binder is such
that the ratio of carboxy group equivalents to hydroxyl group
equivalents is in the range of from about 1/0.65 to 1/0.75.
13. A fiberglass product comprising a mat of glass fibers
containing the binder of claim 1.
14. The fiberglass product of claim 13, wherein the product is
building insulation.
15. The fiberglass product of claim 13, wherein the product is
reinforcing mat for roofing or flooring.
16. The fiberglass product of claim 13, wherein the product is a
microglass-based substrate useful for printed circuit boards or
battery separators, filter stock, tape stock or reinforcement
scrim.
17. The fiberglass product of claim 13, wherein the product is
filter stock.
18. A fiberglass product prepared by using a binder comprised of a
polycarboxy polymer and a polyol, and spraying onto the product a
fluorinated polymer.
19. The fiberglass product of claim 18, wherein the product is
thermal or sound insulation, or filtration media for air or
liquids.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The subject invention pertains to polycarboxy polymer
binding resins having improved water repellancy properties. More
particularly, the subject invention pertains to thermosetting,
acrylic acid-based binder resins which cure by crosslinking with a
poly-functional, hydroxyl group-reactive curing agent, which
binders containing such resins exhibit minimal water absorption.
Such binders are useful as replacements for formaldehyde-based
binders in non-woven fiberglass goods.
[0003] 2. Description of the Related Art
[0004] Fiberglass binders have a variety of uses ranging from
stiffening applications where the binder is applied to woven or
non-woven fiberglass sheet goods and cured, producing a stiffer
product; thermo-forming applications wherein the binder resin is
applied to a sheet or lofty fibrous product, following which it is
dried and optionally B-staged to form an intermediate but yet
curable product; and to fully cured systems such as building
insulation.
[0005] Fibrous glass insulation products generally comprise matted
glass fibers bonded together by a cured thermoset polymeric
material. Molten streams of glass are drawn into fibers of random
lengths and blown into a forming chamber where they are randomly
deposited as a mat onto a traveling conveyor. The fibers, while in
transit in the forming chamber and while still hot from the drawing
operation, are sprayed with an aqueous binder. A
phenol-formaldehyde binder has been used throughout the fibrous
glass insulation industry. The residual heat from the glass fibers
and the flow of air through the fibrous mat during the forming
operation are generally sufficient to volatilize the majority to
all of the water from the binder, thereby leaving the remaining
components of the binder on the fibers as a viscous or semi-viscous
high solids liquid. The coated fibrous mat is transferred to a
curing oven where heated air, for example, is blown through the mat
to cure the binder and rigidly bond the glass fibers together.
[0006] Fiberglass binders used in the present sense should not be
confused with matrix resins which are an entirely different and
non-analogous field of art. While sometimes termed "binders",
matrix resins act to fill the entire interstitial space between
fibers, resulting in a dense, fiber reinforced product where the
matrix must translate the fiber strength properties to the
composite, whereas "binder resins" as used herein are not
space-filling, but rather coat only the fibers, and particularly
the junctions of fibers. Fiberglass binders also cannot be equated
with paper or wood product "binders" where the adhesive properties
are tailored to the chemical nature of the cellulosic substrates.
Many such resins are not suitable for use as fiberglass binders.
One skilled in the art of fiberglass binders would not look to
cellulosic binders to solve any of the known problems associated
with fiberglass binders.
[0007] Binders useful in fiberglass insulation products generally
require a low viscosity in the uncured state, yet characteristics
so as to form a rigid thermoset polymeric mat for the glass fibers
when cured. A low binder viscosity in the uncured state is required
to allow the mat to be sized correctly. Also, viscous binders tend
to be tacky or sticky and hence they lead to accumulation of fiber
on the forming chamber walls. This accumulated fiber may later fall
onto the mat causing dense areas and product problems. A binder
which forms a rigid matrix when cured is required so that a
finished fiberglass thermal insulation product, when compressed for
packaging and shipping, will recover to its as-made vertical
dimension when installed in a building.
[0008] From among the many thermosetting polymers, numerous
candidates for suitable thermosetting fiberglass binder resins
exist. However, binder-coated fiberglass products are often of the
commodity type, and thus cost becomes a driving factor, generally
ruling out such resins as thermosetting polyurethanes, epoxies, and
others. Due to their excellent cost/performance ratio, the resins
of choice in the past have been phenol/formaldehyde resins.
Phenol/formaldehyde resins can be economically produced, and can be
extended with urea prior to use as a binder in many applications.
Such urea-extended phenol/formaldehyde binders have been the
mainstay of the fiberglass insulation industry for years, for
example.
[0009] Over the past several decades however, minimization of
volatile organic compound emissions (VOCs) both on the part of the
industry desiring to provide a cleaner environment, as well as by
Federal regulation, has led to extensive investigations into not
only reducing emissions from the current formaldehyde-based
binders, but also into candidate replacement binders. For example,
subtle changes in the ratios of phenol to formaldehyde in the
preparation of the basic phenol/formaldehyde resole resins, changes
in catalysts, and addition of different and multiple formaldehyde
scavengers, has resulted in considerable improvement in emissions
from phenol/formaldehyde binders as compared with the binders
previously used. However, with increasingly stringent Federal
regulations, more and more attention has been paid to alternative
binder systems which are free from formaldehyde.
[0010] One such candidate binder system employs polymers of acrylic
acid as a first component, and a polyol such as glycerine or a
modestly oxyalkylated glycerine as a curing or "crosslinking"
component. The preparation and properties of such poly(acrylic
acid)-based binders, including information relative to the VOC
emissions, and a comparison of binder properties versus urea
formaldehyde binders is presented in "Formaldehyde-Free
Crosslinking Binders For Non-Wovens", Charles T. Arkins et al.,
TAPPI JOURNAL, Vol. 78, No.11, pages 161-168, November 1995. The
binders disclosed by the Arkins article, appear to be B-stageable
as well as being able to provide physical properties similar to
those of urea/formaldehyde resins.
[0011] U.S. Pat. No. 5,340,868 discloses fiberglass insulation
products cured with a combination of a polycarboxy polymer,
a-hydroxyalkylamide, and an at least one trifunctional monomeric
carboxylic acid such as citric acid. The specific polycarboxy
polymers disclosed are poly(acrylic acid) polymers. See also, U.S.
Pat. No. 5,143,582
[0012] U.S. Pat. No. 5,318,990 discloses a fibrous glass binder
which comprises a polycarboxy polymer, a monomeric trihydric
alcohol and a catalyst comprising an alkali metal salt of a
phosphorous-containing organic acid.
[0013] Published European Patent Application EP 0 583 086 Al
appears to provide details of polyacrylic acid binders whose cure
is catalyzed by a phosphorus-containing catalyst system as
discussed in the Arkins article previously cited. Higher molecular
weight poly(acrylic acids) are stated to provide polymers
exhibiting more complete cure. See also U.S. Pat. Nos. 5,661,213;
5,427,587; 6,136,916; and 6,221,973.
[0014] Some polycarboxy polymers have been found useful for making
fiberglass insulation products. Problems of clumping or sticking of
the glass fibers to the inside of the forming chambers during the
processing, as well as providing a final product that exhibits the
recovery and rigidity necessary to provide a commercially
acceptable fiberglass insulation product, have been overcome. See,
for example, U.S. Pat. No. 6,331,350. The thermosetting acrylic
resins have been found to be more hydrophilic than the traditional
phenolic binders, however. This hydrophilicity can result in
fiberglass insulation that is more prone to absorb iiquid water,
thereby possibly compromising the integrity of the product. Also,
the thermosetting acrylic resins now being used as binding agents
for fiberglass have been found to not react as effectively with
silane coupling agents of the type traditionally used by the
industry. The addition of silicone as a hydrophobing agent results
in problems when abatement devices are used that are based on
incineration. Also, the presence of silicone in the manufacturing
process can interfere with the adhesion of certain facing
substrates to the finished fiberglass material. Overcoming these
problems will help to better utilize polycarboxy polymers in
fiberglass binders.
[0015] Accordingly, it is an objective of the present invention to
provide a novel, non-phenol/formaldehyde binder.
[0016] Yet another object of the present invention is to provide
such a binder which allows one to prepare fiberglass insulation
products which are more water repellent and less prone to absorb
liquid water.
[0017] Still another object of the present invention is to provide
a fiberglass insulation product which exhibits good recovery and
rigidity, is formaldehyde-free, and is more water-proof.
[0018] These and other objects of the present invention will become
apparent to the skilled artisan upon a review of the following
description and the claims appended hereto.
SUMMARY OF THE INVENTION
[0019] In accordance with the foregoing objectives, there is
provided by the present invention a novel fiberglass binder. The
binder composition of the present invention comprises a polycarboxy
polymer, a polyol, and a fluorinated polymer. It is also preferred
that the binder comprise a catalyst, such as an alkaline metal salt
of a phosphorus-containing organic acid.
[0020] An important aspect of the binder of the present invention
is that the binder composition, in addition to the polycarboxy
polymer and the polyol, contains a fluorinated polymer. The
presence of the fluorinated polymer in the binder is believed to
render the binder, and hence the fiberglass mat to which the binder
is applied, essentially waterproof. As a result, fiberglass
insulation made with the binder of the present invention avoids the
possible problem of coming apart when subjected to water, as the
binder of the present invention has been found to repel the water
and maintain the integrity of the bond with the fiberglass.
[0021] Among other things, it has been discovered that by including
a fluorinated polymer in a formaldehyde free binder for glass
fibers, and in particular a polycarboxy/polyol binder, water
repellency for the fiberglass mats prepared are achieved without
adversely effecting performance or processing. The glass fiber mats
can be used as thermal or sound insulation, as well as filtration
media in filtering air or liquids.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] The binder of interest with regard to the present invention
is a formaldehyde free binder useful for glass fibers. Of
particular interest is a binder composition compound of a
polycarboxy polymer and a polyol. Such binder compositions are
described, for example, in U.S. Pat. No.6,331,350, which is hereby
expressly incorporated by reference in its entirety.
[0023] The polycarboxy polymer used in the preferred binder of the
present invention comprises an organic polymer or oligomer
containing more than one pendant carboxy group. The polycarboxy
polymer may be a homopolymer or copolymer prepared from unsaturated
carboxylic acids including but not necessarily limited to, acrylic
acid, methacrylic acid, crotonic acid, isocrotonic acid, maleic
acid, cinnamic acid, 2-methylmaleic acid, itaconic acid,
2-methylitaconic acid, -methyleneglutaric acid, and the like.
Alternatively, the polycarboxy polymer may be prepared from
unsaturated anhydrides including, but not necessarily limited to,
maleic anhydride, methacrylic anhydride, and the like, as well as
mixtures thereof. Methods for polymerizing these acids and
anhydrides are well-known in the chemical art.
[0024] The polycarboxy polymer of the present invention may
additionally comprise a copolymer of one or more of the
aforementioned unsaturated carboxylic acids or anhydrides and one
or more vinyl compounds including, but not necessarily limited to,
styrene, -methylstyrene, acrylonitrile, methacrylonitrile, methyl
acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate,
methyl methacrylate, n-butyl methacrylate, isobutyl methacrylate,
glycidyl methacrylate, vinyl methyl ether, vinyl acetate, and the
like. Methods for preparing these copolymers are well-known in the
art.
[0025] Preferred polycarboxy polymers comprise homopolymers and
copolymers of polyacrylic acid. It is particularly preferred that
the molecular weight of the polycarboxy polymer, and in particular
polyacrylic acid polymer, is less than 10000, more preferably less
than 5000, and most preferably about 3000 or less. The low
molecular weight polycarboxy polymer results in a final product
which exhibits excellent recovery and rigidity.
[0026] The formaldehyde-free curable aqueous binder composition of
the present invention also contains a polyol containing at least
two hydroxyl groups. The polyol must be sufficiently nonvolatile
such that it will substantially remain available for reaction with
the polyacid in the composition during heating and curing
operations. The polyol may be a compound with a molecular weight
less than about 1000 bearing at least two hydroxyl groups such as,
for example, ethylene glycol, glycerol, pentaerythritol,
trimethylol propane, sorbitol, sucrose, glucose, resorcinol,
catechol, pyrogallol, glycollated ureas, 1,4-cyclohexane diol,
diethanolamine, triethanolamine, and certain reactive polyols such
as, for example, -hydroxyalkylamides such as, for example,
bis[N,N-di(-hydroxyethyl)]adipamide, as may be prepared according
to the teachings of U.S. Pat. No. 4,076,917, hereby incorporated
herein by reference in its entirety, or it may be an addition
polymer containing at least two hydroxyl groups such as, for
example, polyvinyl alcohol, partially hydrolyzed polyvinyl acetate,
and homopolymers or copolymers of hydroxyethyl (meth) acrylate,
hydroxypropyl(meth) acrylate, and the like. The most preferred
polyol for the purposes of the present invention is triethanolamine
(TEA).
[0027] The ratio of the number of equivalents of carboxy,
anhydride, or salts thereof of the polyacid to the number of
equivalents of hydroxyl in the polyol is from about 1/0.01 to about
1/3. An excess of equivalents of carboxy, anhydride, or salts
thereof of the polyacid to the equivalents of hydroxyl in the
polyol is preferred, however, thus, a more preferred ratio of the
number of equivalents of carboxy, anhydride, or salts thereof in
the polyacid to the number of equivalents of hydroxyl in the polyol
is from about 1/0.2 to about 1/0.95, more preferably from 1/0.6 to
1/0.8, and most preferably from 1/0.65 to 1/0.75. A low ratio,
approaching 1/0.7 has been found to be of particular advantage
especially when combined with a low molecular weight polycarboxy
polymer as described above, and also preferably with a lower pH
binder.
[0028] It is most preferred that the pH of the binder of the
present invention also be low, i.e., no greater than 4.5, and
preferably less than 3.5, for it has been found that the
combination of low molecular weight polycarboxy polymer with a
lowered pH provides a binder exhibiting minimal processing
difficulties and a final product with excellent recovery and
rigidity. Maintaining the pH in the range of from 3.5 to 4.5 allows
one to avoid serious problems with corrosion of the equipment while
still realizing the benefits of the low pH. However, a lower pH can
also be used, e.g., less than 3.5, and is actually preferred due to
beneficial results, with appropriate handling precautions.
[0029] An important aspect of the present invention is that the
binder of the present invention also contains a fluorinated
polymer, as an additive. The presence of the fluorinated polymer
has been found to render the polycarboxy/polyol binder of the
present invention less prone to absorb water, while still allowing
excellent products and good processing of those products, e.g.,
thermal and sound insulation products and filtration media in
filtering air or liquids. As a result, its presence may better
maintain the integrity of the bond between the binder and glass
fiber, and hence the integrity of the entire mat product, when
exposed to liquid water. The binder bond, and hence the overall
product, is more water-proof.
[0030] The preferred fluorinated polymer is a copolymer prepared
from a fluorine containing acrylate monomer with styrene or some
other commonly used acrylate comonomer. Such fluorinated polymers
are available, for example, under the trademark ParaChem
RD-F25.TM.. Generally, any suitable fluorine-containing polymer in
which fluorine has been substituted for hydrogen in an organic
polymer can be employed. This would include the vinyl fluoride
polymers and the tetrafluoroethylene polymers. Among the
tetrafluoroethylene polymers, the homopolymers of
tetrafluoroethylene, as well as its copolymers with
hexafluoropropylene, perfluorovinylether and ethylene can also be
used to impart hydrophobicity to the polycarboxy/polyol binder of
the present invention.
[0031] The fluorinated polymers employed are generally added to the
polycarboxy/polyol binder as a dispersion or emulsion, and can be
added directly to the binder composition which is then employed in
the formation of the fiberglass products. Alternatively, the
fluorinated polymer can be sprayed onto the fiberglass product
itself once it has been formed and cured. A combination of these
two events can also be employed. It is preferred, however, that the
fluorinated polymer be added directly to the binder composition
used in the formation of the fiberglass product.
[0032] The amount of fluorinated polymer employed is generally such
that the final fiberglass product contains from 0.005 to 0.5 wt. %
of the fluorine-containing polymer. More preferably, the amount of
fluorine-containing polymer in the final product can generally
range from about 0.01 to about 0.3 wt. %, even more preferably from
about 0.04 to 0.1 wt. %, and most preferably in the range of about
0.05 to 0.09 wt. %. It has been found that the use of the
fluorine-containing polymer can be at levels much lower than
silicone materials to achieve similar water repellency, while also
overcoming the problems often inherent in using silicone
hydrophobing agents. Use of the more preferred ranges, e.g., from
0.05 to 0.09 wt. % of the fluorine-containing polymer, offers
excellent water repellency while using only a small amount of the
additive, thus making the use economical as well.
[0033] It is preferred that the formaldehyde-free curable aqueous
binder composition of the present invention also contain a
catalyst. Most preferably, the catalyst is a phosphorous-containing
accelerator which may be a compound with a molecular weight less
than about 1000 such as, for example, an alkali metal
polyphosphate, an alkali metal dihydrogen phosphate, a
polyphosphoric acid, and an alkyl phosphinic acid or it may be an
oligomer or polymer bearing phosphorous-containing groups such as,
for example, addition polymers of acrylic and/or maleic acids
formed in the presence of sodium hypophosphite, addition polymers
prepared from ethylenically unsaturated monomers in the presence of
phosphorous salt chain transfer agents or terminators, and addition
polymers containing acid-functional monomer residues such as, for
example, copolymerized phosphoethyl methacrylate, and like
phosphonic acid esters, and copolymerized vinyl sulfonic acid
monomers, and their salts. The phosphorous-containing accelerator
may be used at a level of from about 1% to about 40%, by weight
based on the combined weight of the polyacid and the polyol.
Preferred is a level of phosphorous-containing accelerator of from
about 2.5% to about 10%, by weight based on the combined weight of
the polyacid and the polyol.
[0034] The formaldehyde-free curable aqueous binder composition may
contain, in addition, conventional treatment components such as,
for example, emulsifiers, pigments, filler, anti-migration aids,
curing agents, coalescents, wetting agents, biocides, plasticizers,
organosilanes, anti-foaming agents, colorants, waxes, and
anti-oxidants.
[0035] The formaldehyde-free curable aqueous binder composition may
be prepared by admixing the polyacid of the present invention, the
polyol, and the phosphorous-containing accelerator using
conventional mixing techniques. In another embodiment, a carboxyl-
or anhydride-containing addition polymer and a polyol may be
present in the same addition polymer, which addition polymer would
contain both carboxyl, anhydride, or salts thereof functionality
and hydroxyl functionality. In another embodiment, the salts of the
carboxy-group are salts of functional alkanolamines with at least
two hydroxyl groups such as, for example, diethanolamine,
triethanolamine, dipropanolamine, and di-isopropanolamine. In an
additional embodiment, the polyol and the phosphorous-containing
accelerator may be present in the same addition polymer, which
addition polymer may be mixed with the modified polyacid of the
present invention. In yet another embodiment the carboxyl- or
anhydride-containing addition polymer, the polyol, and the
phosphorous-containing accelerator may be present in the same
addition polymer. Other embodiments will be apparent to one skilled
in the art. As disclosed herein-above, the carboxyl groups of the
polyacid may be neutralized to an extent of less than about 35%
with a fixed base before, during, or after the mixing to provide
the aqueous composition. Neutralization may be partially effected
during the formation of the polyacid.
[0036] Once the composition of the polyacid, the polyol and the
fluorinated polymer has been prepared, in a preferred embodiment,
other additives, can then be mixed in with the composition to form
the final composition to be sprayed on the fiberglass. As molten
streams of glass are drawn into fibers of random lengths and blown
into a forming chamber where they are randomly deposited as a mat
onto a traveling conveyor, the fibers, while in transit in the
forming chamber, are sprayed with the aqueous binder composition of
the present invention, which includes the modified polyacid.
[0037] More particularly, in the preparation of fiberglass
insulation products, the products can be prepared using
conventional techniques. As is well known, a porous mat of fibrous
glass can be produced by fiberizing molten glass and immediately
forming a fibrous glass mat on a moving conveyor. The expanded mat
is then conveyed to and through a curing oven wherein heated air is
passed through the mat to cure the resin. The mat is slightly
compressed to give the finished product a predetermined thickness
and surface finish. Typically, the curing oven is operated at a
temperature from about 150.quadrature.C to about 325.quadrature.C.
Preferably, the temperature ranges from about 180.quadrature. to
about 225.quadrature.C. Generally, the mat resides within the oven
for a period of time from about 1/2 minute to about 3 minutes. For
the manufacture of conventional thermal or acoustical insulation
products, the time ranges from about 3/4 minute to about 11/2
minutes. The fibrous glass having a cured, rigid binder matrix
emerges from the oven in the form of a bat which may be compressed
for packaging and shipping and which will thereafter substantially
recover its vertical dimension when unconstrained.
[0038] The formaldehyde-free curable aqueous composition may also
be applied to an already formed nonwoven by conventional techniques
such as, for example, air or airless spraying, padding, saturating,
roll coating, curtain coating, beater deposition, coagulation, or
the like.
[0039] The waterborne formaldehyde-free composition of the present
invention, after it is applied to a nonwoven, is heated to effect
drying and curing. The duration and temperature of heating will
affect the rate of drying, processability and handleability, and
property development of the treated substrate. Heat treatment at
about 120.quadrature.C, to about 400.quadrature.C, for a period of
time between about 3 seconds to about 15 minutes may be carried
out; treatment at about 150.quadrature.C, to about
250.quadrature.C, is preferred. The drying and curing functions may
be effected in two or more distinct steps, if desired. For example,
the composition may be first heated at a temperature and for a time
sufficient to substantially dry but not to substantially cure the
composition and then heated for a second time at a higher
temperature and/or for a longer period of time to effect curing.
Such a procedure, referred to as "B-staging", may be used to
provide binder-treated nonwoven, for example, in roll form, which
may at a later stage be cured, with or without forming or molding
into a particular configuration, concurrent with the curing
process.
[0040] The heat-resistant nonwovens may be used for applications
such as, for example, insulation batts or rolls, as reinforcing mat
for roofing or flooring applications, as roving, as
microglass-based substrate for printed circuit boards or battery
separators, as filter stock, as tape stock, as tape board for
office petitions, in duct liners or duct board, and as
reinforcement scrim in cementitious and non-cementitious coatings
for masonry. Most preferably, the products are useful as thermal or
sound insulation. The nonwovens can also be used as filtration
media for air and liquids.
[0041] The present invention will be further illustrated by the
following example, which is in no manner meant to be limiting in
scope.
EXAMPLE
[0042] An emulsified copolymer of fluorine-containing acrylate
monomer with styrene, available under the trademark ParaChem
RD-F25.TM., was added to a polyacrylic acid/polyol binder in a
fiberglass building product manufacturing process, where the final
insulation product contained approximately 5% binder content by
weight. The fluorine-containing polymer was added to the binder in
several levels to produce samples of R19 insulation containing
various levels of the fluorine-containing polymer additive. A run
was also made where a silicone hydophobing agent was added such
that the final product contained 0.09 wt. % of the silicone
additive. All of the samples were tested for water repellency by
measuring water pickup by weight. This was achieved by taking a
6-inch by 6-inch square of the fiberglass product and placing it
into a bath of water for five minutes. After that time, the
fiberglass was removed and suspended for 30 seconds from one corner
to allow draining. After the 30 seconds, the fiberglass sample was
then weighed. The weight gain was recorded as a percent of the
original weight. The results are shown below: TABLE-US-00001
Additive Percent Sample (based on final product) Weight Gain
Percent control 0.09 70 (silicone additive) 1 0.09 38 2 0.06 63 3
0.04 245 4 0 1900
[0043] The foregoing results with regard to samples 1, 2 and 3, as
compared to the control and sample 4 (which contained no additive)
demonstrate that the fluorinated additive of the present invention
can achieve water repellency, even at reduced levels compared to
that of silicone.
[0044] While the invention has been described with preferred
embodiments, it is to be understood that variations and
modifications may be resorted to as will be apparent to those
skilled in the art. Such variations and modifications are to be
considered within the purview and the scope of the claims appended
hereto.
* * * * *