KR20070088596A - Water repellant fiberglass binder comprising a fluorinated polymer - Google Patents

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.

Description

WATER REPELLANT FIBERGLASS BINDER COMPRISING A FLUORINATED POLYMER}

The present invention relates to a polycarboxy polymer bonded resin with improved water repellent properties. More specifically, the present invention relates to a thermosetting, acrylic acid-based binder resin that cures by crosslinking with a polyfunctional, hydroxyl group reactive curing agent, the binder comprising a resin exhibiting minimal water absorption. do. Such binders are useful as substitutes for formaldehyde-based binders in articles made of nonwoven glass fibers.

The fiberglass binder is applied to a sheet or a high quality fiber product from the application of a curing binder which is applied to a woven or nonwoven fiberglass sheet product to produce a cured product, which is then dried and optionally subjected to a B-step. It is a curable product but has a wide range of uses in areas ranging from thermoforming applications to intermediate materials and to fully cured systems such as building insulation.

Fibrous glass insulating articles generally comprise glass fibers mated together by a cured thermoset polymeric material. The molten flow of glass penetrates into the fibers at an inconsistent length and is irregularly stacked as a mat on a moving conveyor.

This fiber is sparged with an aqueous binder while still hot in the transit in the forming chamber and in the stretching operation. Phenol-formaldehyde binders have been used throughout the fibrous glass insulation industry. Residual heat from the glass fibers and the flow of air through the fibrous mat during the molding operation is generally sufficient to volatize most of all the water from the binder, whereby the remaining components of the binder on the fibers are viscous or semi-viscous high solid liquid Left. The applied fibrous mat is for example transferred to a curing oven where heated air is blown into the mat to cure the binder to tightly bond the glass fibers together.

The glass fiber binders used in this respect should be distinguished from matrix resins, which are completely different and non-similar technical fields. Sometimes referred to as a "binder", the matrix resin acts to fill all the gaps between the fibers so that in terms of density a fiber reinforced product is obtained which necessarily transforms the fiber strength properties into a composite, "Binder resin" is not a space filler, but rather merely applies the fibers and in particular the junctions of the fibers. Glass fiber binders also cannot be equivalent to paper or wood product "binders" where bonding properties are tailored to the chemical properties of the cellulosic substrate. Many such resins are not suitable for use as glass fiber binders. One skilled in the art of glass fiber binders will not seek a cellulosic binder to solve any known problem with glass fiber binders.

Binders useful in glass fiber insulating articles generally require low viscosity in the cured state, but require properties to form a rigid thermoset polymeric mat for the glass fiber when cured. Low binder viscosity is required in the uncured state to ensure that the mat is the correct size. Viscous binders also tend to be tacky or sticky, so they result in the accumulation of fibers on the wall surface of the forming chamber. This accumulated fiber can later fall on the mat, causing density areas and product issues. When cured, a binder that forms a rigid matrix is required and as a result the compressed fiberglass thermal insulation finished product for packaging or shipping will be restored to its original thickness when installed in the building.

Among many thermoset polymers, there are a number of alternatives to suitable thermoset glass fiber binder resins. However, binder-coated glass fiber products are sometimes of one commodity type and therefore cost is a major driving factor and generally excludes such resins as thermoset polyurethanes, epoxies and the like. Due to their superior cost / performance ratio, the resin chosen in the past was phenol / formaldehyde resin. Phenol / formaldehyde resins can be produced inexpensively and stretched to urea before being used as binders in many applications. For example, such urea-extending phenol / formaldehyde binders have been a major part of the fiberglass insulation industry for many years.

However, over the past decades, minimization of volatile organic compound emissions (VOCs) by protons, as well as by provincial regulations and in industrial sectors that wish to provide a clean environment, not only reduces emissions from current formaldehyde-based binders, but also binders. Led extensive research into alternative candidates. For example, in the preparation of basic phenol / formaldehyde resole resins, subtle changes in the ratio of phenol to formaldehyde, changes in crystals, and the addition of other multiple formaldehyde scavengers are compared to the previously used binders. There has been a significant improvement in release from the formaldehyde binder. However, due to increasingly stringent federal regulations, even more attention has been given to alternative binder systems that are free of formaldehyde.

This candidate binder system employs a polymer of acrylic acid as the first component and a polyol such as glycerin or to some extent oxyalkylated glycerin as a curing or "crosslinking" component. The preparation and properties of these poly (acrylic acid) -based binders, including information on VOC emissions, and the comparison of binder properties to urea formaldehyde binders are described by Charles T. Arkins et al, "Formaldehyde-Free Crosslinked Binders (Formaldehyde-Free). Crosslinking Binders For Non-Wovens "(TAPPI JOURNAL, Vol. 78, No. 11, pages 161-168, November 1995). The binder described by the Arkins paper has been shown to be B-stage as well as capable of providing similar physical properties to that of urea / formaldehyde resins.

U.S. Patent No. 5,340,868 describes a glass fiber insulation article cured with a combination of polycarboxylic polymers, a-hydroxy alkylamides, and carboxylic acids of at least one trifunctional monomer, such as citric acid. Particular polycarboxy polymers described are poly (acrylic acid) polymers. U.S. Patent No. See 5,143,582. U.S. Patent No. 5,318,990 describes fibrous glass binders comprising a catalyst comprising a polycarboxy polymer, a trihydric alcohol of a monomer and an alkali metal salt of a phosphorus-containing organic acid.

Published European patent application EP 0 583 086 Al indicates that the curing provides details of the polyacrylic acid binder promoted by the phosphorus-containing catalyst system as described in the Arkins paper cited already. High molecular weight poly (acrylic acid) has been described to provide polymers that show more complete curing. U.S. Patent No. 5,661,213; 5,427,587; 6,136,916; And 6,221,973.

Several polycarboxy polymers have been found that are useful for making glass fiber insulation products. The problem of cohesion or adhesion of the glass fibers to the inner surface of the molding chamber during the manufacturing process, as well as the provision of the final product exhibiting the resilience and strength necessary to provide a commercially acceptable glass fiber insulating product, has been overcome. For example, U.S. Patent No. See 6,331,350. However, it has been found that thermosetting acrylic resins are more hydrophilic than conventional phenolic binders. This hydrophilicity is more prone to absorbing water in liquids and can thereby lead to fiberglass insulation which promises product integrity. It has also been found that thermosetting acrylic resins, which are now used as binders for glass fibers, do not react effectively with silane coupling agents, a form traditionally used in the industry. The addition of silicon as a hydrophobic agent leads to problems related to incineration when mitigating devices are used. In addition, the presence of silicon during the manufacturing process can interfere with the bonding of any opposing substrate to the finished fiberglass material. Overcoming these problems will help to better utilize polycarboxy polymers in glass fiber binders.

It is an object of the present invention to provide novel non-phenol / formaldehyde binders.

It is another object of the present invention to provide a binder which makes it possible to produce glass fiber insulation products which are better repellent in water and less prone to absorbing liquid water.

It is a further object of the present invention to provide a glass fiber insulating article which exhibits good resilience and strength, is free of formaldehyde and is more waterproof.

These and other objects of the present invention will become apparent to those skilled in the art upon review of the following detailed description and claims appended hereto.

In accordance with the above object, a novel glass fiber binder is provided by the present invention. The binder composition of the present invention comprises a polycarboxy polymer, a polyol, and a fluorinated polymer. It is also preferred that the binder comprises a catalyst such as an alkali metal salt of a phosphorus-containing organic acid.

An important aspect of the binder of the present invention is that in addition to polycarboxy polymers and polyols, the binder composition comprises a fluorinated polymer. The presence of fluorinated polymers in the binder imparts water resistance to the binder and has been shown to impart essentially water resistance to the glass fiber mat to which the binder is applied. As a result, the glass fiber insulator made of the binder of the present invention eliminates possible problems that come when applied to water, because the binder of the present invention repels water and maintains the integrity of the bond with the glass fiber.

Alternatively, it has been found that water repellency for glass fiber mats made of formaldehyde-free binders for glass fibers, and in particular fiberglass mats made of fluorinated polymers in polycarboxy / polyol binders, can be achieved without performing or progressing adverse effects. . Fiberglass mats can be used as heat dissipation or soundproofing materials as well as as a filter medium for filtering air or liquid.

The subject binder according to the present invention is a formaldehyde free binder useful for glass fibers. Particularly targeted are binder composition compounds of polycarboxy polymers and polyols. Such binder compositions are described, for example, in U.S. Pat. Patent No. 6,331,350 is described.

The polycarboxy polymers used in the preferred binders of the present invention include organic polymers or oligomers comprising more than one pendant carboxyl group. Polycarboxy polymers include, but are not necessarily limited to, acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, maleic acid, cinnamic acid, 2-methylmaleic acid, itaconic acid, 2-methylitaconic acid, 2-methyleneglutar Homopolymers or copolymers prepared from unsaturated carboxylic acids, including acids and the like. Alternatively, polycarboxy polymers can be prepared from unsaturated anhydrides including but not limited to maleic anhydride, methacrylic anhydride and the like, as well as mixtures thereof. Methods of polymerizing these acids and anhydrides are well known in the chemical art.

The polycarboxy polymers of the present invention include, but are not necessarily limited to, one or more unsaturated carboxylic acids or anhydrides mentioned above, styrene, -methylstyrene, acrylonitrile, methacrylonitrile, methyl acrylate, ethyl acrylate, one or more vinyl compounds including n-butyl acrylate, isobutyl acrylate, methyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, glycidyl methacrylate, vinyl methyl ether, vinyl acetate and the like It may additionally include a copolymer of. Methods of making these copolymers are well known in the art.

Preferred polycarboxy polymers include homopolymers and copolymers of polyacrylic acid. Particular preference is given to the molecular weight of the polycarboxy polymer, and in particular the polyacrylic acid polymer, to be less than 10000, more preferably less than 5000, and most preferably about 3000 or less. Low molecular weight polycarboxy polymers can provide end products that exhibit good resilience and strength.

The formaldehyde-free curable aqueous binder composition of the present invention also includes a polyol containing at least two hydroxyl groups. Since this polyol is clearly nonvolatile, it remains substantially available for reaction with the polyacid in the composition during the heating and curing operation. This polyol is for example ethylene glycol, glycerol, pentaerythritol, trimethylol propane, sorbitol, sucrose, glucose, resorcinol, catechol, pyrogallol, glycolated urea, 1,4-cyclohexane diol, It may be a compound having a molecular weight of less than about 1000 having at least two hydroxyl groups, such as diethanolamine, triethanolamine, and certain reactive polyols such as, for example, -hydroxyalkylamides, for example bis [N, N US-incorporated herein by reference in its entirety, such as -di (-hydroxyethyl)] adifamide Patent No. 4,076,917 or may be prepared, for example, with polyvinyl alcohol, partially hydrolyzed polyvinyl acetate, and homopolymers of hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate Or an addition polymer comprising at least two hydroxyl groups, such as copolymers and the like. Most preferred polyols for the purposes of the present invention are triethanolamine (TEA).

The ratio of the equivalent value of carboxyl, anhydride or salts thereof to the equivalent value of hydroxyl groups in this polyol is from about 1 / 0.01 to about 1/3. However, since the equivalent of carboxyl, anhydride or salts of these polyacids to the equivalent of hydroxyl groups in this polyol is preferred, the equivalent of carboxyl, anhydride or salts thereof in this polyacid to the equivalent of hydroxyl groups in this polyol The more preferable ratio of is 1 / 0.2 to 1 / 0.95, more preferably 1 / 0.6 to 1 / 0.8, and most preferably 1 / 0.65 to 1 / 0.75. Low ratios approaching 1 / 0.7 have been found to be particularly beneficial when particularly combined with low molecular weight polycarboxy polymers as described above and also preferably with lower pH binders.

The pH of the binder of the present invention is also low, for example not greater than 4.5, preferably less than 3.5, and the combination of lower pH and lower molecular weight polycarboxy polymers exhibits minimal processing difficulty. It has been found to provide a final product with a binder and good resilience and strength. Keeping the pH in the range of 3.5 to 4.5 allows to avoid the serious problems of equipment corrosion while still realizing the benefits of low pH. However, lower pHs, for example lower than 3.5, may also be used, and precisely lower pHs are preferred due to the beneficial results with proper operational attention.

An important aspect of the present invention is that the binder of the present invention also includes a fluorinated polymer as an additive. The presence of fluorinated polymers absorbs water into the polycarboxy / polyol binders of the present invention while still allowing for good processability, such as heat dissipating and soundproofing products and filter media for filtering air or liquids, and good processability of these products. It has been found that there is little tendency to do so. As a result, its presence can better maintain the integrity of the bond between the binder and the glass fibers, and thus better maintain the original form of the entire mat product when exposed to liquid water. This binder bond, and thus the entire product, is more waterproof.

Preferred fluorinated polymers are copolymers made from fluorine, including acrylate monomers with styrene or other commonly used acrylate comonomers. Such fluorinated polymers can be used, for example, under the trademark ParaChem RD-F25.

In general, suitable fluorine-containing polymers in which fluorine is substituted for hydrogen in the organic polymer may be employed. This will include vinyl fluorinated polymers and tetrafluoroethylene polymers. In this tetrafluoroethylene polymer, not only homopolymers of tetrafluoroethylene but also copolymers with hexafluoropropylene, perfluorovinylether and ethylene can be used to impart hydrophobicity to the polycarboxy / polyol binders of the present invention. have.

The fluorinated polymer employed can generally be added to the polycarboxy / polyol binder as a dispersion or emulsion and then directly added to the binder composition employed in the formation of the glass fiber product. Alternatively, the fluorinated polymer can itself be sprayed onto the glass fibers once it has been molded and cured. Combinations of these two may also be employed. However, it is preferred that the fluorinated polymer is added directly to the binder composition used in the molding of the fiberglass article.

The amount of fluorinated polymer used is generally such that the final glass fiber product comprises from 0.005 to 0.5% by weight of fluorine-containing polymer. More preferably, the amount of fluorine-containing polymer in the final product is in the range of about 0.01 to about 0.3 weight percent, more preferably about 0.04 to about 0.1 weight percent, and most preferably about 0.05 to about 0.09 weight percent. Will be. It has been found that the amount of fluorine-containing polymer can be at a much lower level than silicone materials to achieve similar water repellency and to overcome the problems inherent in using silicone hydrophobic formulations. A more preferred range of uses, for example 0.05 to 0.09% by weight of the fluorine-containing polymer, can be used very economically because it provides good water repellency while using only a small amount of additives.

It is preferred that the formaldehyde-free curable aqueous binder composition of the present invention also includes a catalyst. Most preferably, the catalyst is a phosphorus-containing accelerator, which may be a compound having a molecular weight less than about 1000, such as, for example, alkali metal polyphosphate, alkali metal dihydrogen phosphate, polyphosphoric acid, and alkyl phosphinic acid, or For example, addition polymers made from ethylenically unsaturated monomers in the presence of acrylic and / or maleic acid addition polymers formed in the presence of sodium hypophosphite, phosphate chain transfer agents or terminators, and copolymerized, for example Oligomers or polymers carrying a phosphorus-containing group, such as addition polymers comprising acid-functional monomer residues such as phosphoethyl methacrylate, phosphonic acid esters, copolymerized vinyl sulfonic acid monomers, and salts thereof. Phosphorus-containing accelerators may be used at levels of about 1% to about 40% by weight based on the combined weight of the polyacid and the polyol. Preferably from about 2.5% to about 10% by weight of the phosphorus-containing accelerator is based on the combined weight of the polyacid and the polyol.

Formaldehyde-free curable aqueous binder compositions may additionally include, for example, emulsifiers, pigments, filters, anti-migration aids, curing agents, coalescing agents, wetting agents, insecticides, plasticizers, organosilanes, antifoaming agents, coloring agents, waxes and anti- -Conventional processing components such as oxidants.

Formaldehyde-free curable aqueous binder compositions can be prepared by mixing the polyacids, polyols, and phosphorus-containing accelerators of the present invention with one another using conventional mixing techniques. In another embodiment, the carboxyl- or anhydride-containing addition polymer and the polyol may be present as the same addition polymer in which the addition polymer may comprise both carboxyl, anhydride or their salt functionality and hydroxyl functionality.

In another embodiment, the salt of the carboxyl-group is a salt of a functional alkanolamine having at least two hydroxyl groups such as, for example, diethanolamine, triethanolamine, dipropanolamine, and di-isopropanolamine. In additional embodiments, the polyols and phosphorus-containing accelerators may be present in the same addition polymer in which the addition polymer may be mixed with the investigated polyacids of the present invention.

Furthermore, in another embodiment, the carboxyl- or anhydride-containing addition polymer, polyol and phosphorus-containing accelerator may be present in the same addition polymer. Other embodiments will be apparent to those skilled in the art.

As described above, the carboxylic groups of the polyacids can be neutralized to less than about 35% with fixed base before, during or after mixing to provide an aqueous composition. Neutralization may be partially affected during the formation of polyacids.

Once the composition of polyacid, polyol and fluorinated polymer is prepared, in a preferred embodiment, other additives may then be mixed into the composition to form the final composition to be sprayed onto the glass fibers. As the melt flow of glass flows into fibers of inconsistent lengths and is blown into the forming chamber, where they are irregularly stacked on mats on a transfer conveyor, the fibers contain bones containing modified polyacids while in transit in the forming chamber. The aqueous binder composition of the invention is sprayed.

More particularly, in the manufacture of fiberglass insulation products, these products can be manufactured using conventional techniques. As is well known, porous mats of fibrous glass can be produced by fiberizing molten glass and immediately forming a fibrous glass mat on a moving conveyor. The stretched mat is then moved to and passed through a curing oven where heated air passes through the mat to cure the resin. The mat is gently pressed to give the final product the desired thickness and surface finish. Typically, the curing oven is operated at a temperature of about 150 ° C to about 325 ° C.

Preferably, the temperature is in the range of about 180 ° C to about 225 ° C. Generally, the mat remains in the oven for a period of about 30 seconds to about 180 seconds. For the manufacture of conventional thermally or acoustically insulated products, the time ranges from about 45 seconds to about 90 seconds. The fibrous glass with a cured, rigid binder matrix can be squeezed for packaging and shipping, and then exits the oven in the form of a bat that can substantially restore its vertical dimension when the squeezing is released.

Formaldehyde-free curable aqueous compositions may also be applied to nonwovens already formed by conventional techniques such as, for example, air or airless spraying, padding, dipping, roll coating, curtain coating, beater deposition, flocculation, and the like. .

The floating formaldehyde free composition of the present invention, after it is applied to a nonwoven, is heated to give a drying and curing effect. The duration and temperature of the heating will affect the drying rate, processability and operability, and the development of the properties of the treated substrate. A heating temperature at about 120 ° C. to about 400 ° C. and a time between about 3 seconds to about 15 minutes can be performed and treatment at about 150 ° C. to about 250 ° C. is preferred. Drying and curing functions may be in two or more separate steps, if desired.

For example, the composition may first be heated at a temperature and for a time that substantially dryes the composition but does not substantially cure, and then for a second time and / or for a longer time at a higher temperature that affects the cure. Can be heated. This procedure, referred to as "B-step", provides a binder-treated nonwoven, such as, for example, in the form of a roll that can be cured in a later step, with or without shaping or molding into a particular shape simultaneously with the curing process. Can be used for

Heat-resistant nonwovens are, for example, insulated bats or rolls, microglass-based substrates for reinforcement mats, rovings, printed circuit boards or battery separators for application to roofs or floors, filter stocks, tape stocks, office petitions It can be used in tape boards, duct liners or duct boards, and in applications such as reinforcing scrims in architectural cementitious and non-cementitious coatings. Most preferably, this product is useful for heat dissipation or sound insulation. Nonwovens can also be used as filtration media for air and liquids.

The invention will be explained in more detail by the following examples which are not intended to limit the scope of the invention.

ParaChem RD-F25 ^TM to An emulsified copolymer of styrene-containing fluorine-containing acrylate monomer, which was available, was added to the polyacrylic acid / polyol binder in the glass fiber building product manufacturing process, where the final insulation product contained approximately 5% by weight binder content. Fluorine-containing polymers were added to the binder at several levels to produce samples of R19 insulators containing various levels of fluorine-containing polymer additives. The process also allowed the addition of silicone hydrophobic formulation so that the final product contained 0.09 weight percent silicone additive. All samples were tested for water repellency by weighing the water pick up. This test was accomplished by taking each 6 inch square glass fiber product and placing it in a water bath for 5 minutes. After the time elapsed, the glass fiber was moved by hanging for 30 seconds at one corner to be taken out and drained. Then, after 30 seconds, the glass fiber sample was weighed. The weight obtained was recorded as a percentage of the original weight. The result is as follows.

Sample Additive  percentage (Based on final product) Weight gain percent Control (silicone additive) 0.09 70 One 0.09 38 2 0.06 63 3 0.04 245 4 0 1900

The above results for Samples 1, 2 and 3 compared to Control and Sample 4 (without additive) indicate that the fluorinated additive of the present invention was able to achieve water repellency at a reduced level compared to silicone. Prove it.

Although the present invention has been described in the preferred embodiments, it will be understood that variations and modifications may be apparent to those skilled in the art. Such modifications and variations are considered to be within the scope and scope of the claims appended hereto.

The present invention configured as described above can provide a novel non-phenol / formaldehyde binder.

It is also possible to provide a binder capable of producing a glass fiber insulation product which is better in water and less prone to absorbing liquid water.

And provide good resilience and strength, and formaldehyde free and more water resistant fiberglass insulation products.

Claims (19)

A glass fiber binder comprising an aqueous solution of a polycarboxy polymer, a polyol and a fluorinated polymer. The glass fiber binder according to claim 1, wherein the polycarboxy polymer has a molecular weight of less than 5000. The glass fiber binder according to claim 1, wherein the polycarboxy polymer has a molecular weight of less than 3000. The glass fiber binder of claim 1, wherein the binder further comprises a catalyst comprising an alkali metal salt of a phosphorus-containing organic acid. The glass fiber binder according to claim 4, wherein the catalyst is sodium hypophosphite, sodium phosphite, or a mixture thereof. The glass fiber binder according to claim 1, wherein the polyol is triethanolamine. The glass fiber binder according to claim 1, wherein the polycarboxy polymer comprises a homopolymer and / or a copolymer of polyacrylic acid. The glass fiber binder according to claim 1, wherein the amount of polycarboxy polymer and polyol in the binder is such that the ratio of carboxyl group equivalent to hydroxy group equivalent is in the range of about 1 / 0.65 to 1 / 0.75. The glass fiber binder of claim 1 wherein the fluorinated polymer is a fluorinated acrylate copolymer. Homopolymers and / or copolymers of polyacrylic acid, wherein the polyacrylic acid polymer has a molecular weight of 5000 or less, a glass fiber binder comprising an aqueous solution of triethanolamine and a fluorinated polymer. 11. The glass fiber binder of claim 10, wherein the binder further comprises a catalyst comprising an alkali metal salt of a phosphorus-containing organic acid. The glass fiber binder according to claim 10, wherein the amount of polycarboxy polymer and triethanolamine in the binder is such that the ratio of carboxyl group equivalent to hydroxy group equivalent is in the range of about 1 / 0.65 to 1 / 0.75. A glass fiber product comprising a mat of glass fiber containing the binder of claim 1. 15. The fiberglass article of claim 13, wherein the article is a building insulator. 14. The fiberglass article of claim 13, wherein the article is a reinforcing mat for a roof or floor. 15. The fiberglass article of claim 13, wherein the article is a microglass-based substrate for a printed circuit board or battery separator, a filter stock, a tape stock, or a reinforced scrim. 14. The glass fiber article of claim 13, wherein the article is a filter stock. A glass fiber product, characterized in that it is produced by spraying a fluorinated polymer onto a product using a binder comprising a polycarboxy polymer and a polyol. 19. The glass fiber product according to claim 18, wherein the product is heat dissipation or sound insulation, or a filter medium for air or liquid.