CA2617777A1 - Wet formed mat having improved hot wet tensile strengths - Google Patents

Abstract

Wet-laid chopped strand glass mats for use in roofing applications that have improved hot wet tensile strengths are provided. The chopped strand mats are formed by the application or inclusion of at least one coupling agent to the chopped strand mat during a wet-laid mat forming process. The coupling agent may be added to the chopped strand mat as part of a two-part binder composition that includes a binder and at least one coupling agent. Alternatively, the coupling agent may be added directly to the chopped strand mat independent of the binder. As a further alternative, the coupling agent(s) may be added to the white water in the wet-laid mat forming process and incorporated into the formed glass mat via the glass fibers. The binder may be a modified urea-formaldehyde binder, a non-modified urea-formaldehyde binder, and/or a formaldehyde-free binder. The coupling agent(s) may be silane coupling agents and/or reactive siloxanes.

Description

WET FORMED MAT HAVING IMPROVED
HOT WET TENSILE STRENGTHS
TECHNICAL FIELD AND INDUSTRIAL
APPLICABILITY OF THE INVENTION
The present invention relates generally to chopped strand mats utilized in roofing applications, and more particularly, to chopped strand glass mats that have improved hot wet tensile strengths.

BACKGROUND OF THE INVENTION
Glass fibers are conunonly used as reinforcements in the building composite industiy because they do not shrink or stretch in response to changing atmospheric conditions. Roofing materials such as roofing shingles, roll roofing, and commercial roofing, are typically constructed of a glass fiber mat, an asphalt coating on the fibrous mat, and a surface layer of granules embedded in the asphalt coating.

To foim a chopped strand mat suitable for use in a roofing material, glass fibers are first foinied by attenuating streams of a molten glass material from a bushing or orifice.
The molten glass may be attenuated by a winder which collects gathered filaments into a package or by rollers which pull the fibers before they are collected and chopped. An aqueous sizing composition is typically applied to the fibers after they are drawn from the bushing to protect the fibers from breakage during subsequent processing, to retard interfilament abrasion, and to improve the compatibility of the fibers with the matrix resins that are to be reinforced. After the fibers are treated witli the sizing composition, they may be packaged in their wet condition as wet use chopped strand glass (1A7UCS).
The wet, chopped fibers are then dispersed in a water sluny which contains surfactants, viscosity modifiers, dispersants, and/or other chemical agents and agitated to disperse the fibers. The sluriy containing the dispersed fibers is then deposited onto a moving screen where a substantial portion of the water is removed. A polymeric binder is then applied, and the resulting mat is heated to remove the remaining water and cure the binder. A urea-formaldehyde binder is typically utilized due to its low cost.
Next, asphalt is applied to the mat, such as by spraying the asphalt onto one or both sides of the mat or by passing the mat tlirough a bath of molten asphalt to place a layer of asphalt on both sides of the mat. A protective coating of granules may be applied to the asphalt-coated mat. The asphalt-granule coated mat may be used to foi7n a variety of rooflng materials, such as a roofing sliingle.
Properties such as tear strength, diy tensile strength, and wet tensile strength are measured to deteiniine the usefulness of the chopped strand glass mat in roofing applications. One especially important property for a roofing mat is the retention of hot wet tensile strength. The hot wet strength provides an estimation of the durability of the roofing mat. However, some of the conventional binders utilized to foi7n the roofing mats, such as urea-foz7naldehyde resins, tend to deteriorate under wet conditions such as would be found in an external environment in which the roofing mat would be used.
Modifying the urea-formaldehyde binder, such as with a latex modifier, has been found to increase the tear strength as well as the hot tensile strength over umnodified urea-formaldehyde resins.
Other examples of modifying the binder to improve mat properties such as tensile properties and tear strength are set forth below.

U.S. Patent No. 6,642,299 to Wertz et al. discloses an aqueous fiber mat adhesive binder composition that includes a theiynosetting urea-formaldehyde resin and an additive that is either (1) a styrene aciylic acid or styrene aciylate, (2) an adduct of styrene, maleic anhydride, and an acrylic acid or aciylate, or (3) a physical mixture of a styrene aciylic acid or styrene-aciylate copolymer and a styrene-maleic anhydride copolymer.
The binder may be used in the foiniation of glass fiber mats that demonstrate hot tensile strength tensile retention.

U.S. Patent No. 6,566,459 to Dopico et al. discloses a melamine-urea-foimaldehyde resin modified with a cyclic urea prepolymer and sodium metabisulfite. It is asserted that glass mats foi7ned with the modified melaniine-urea-foi7naldehyde resins have improved hot wet tensile strength retention and superior moisture resistance compared to urea-fonnaldehyde resins.

U.S. Patent No. 6,384,116 to Chan et al. describes a binder composition that is foi-med of a urea-formaldehyde resin modified with a water soluble non-ionic amine oxide.
Optionally, the urea-formaldehyde resin may be fiu-ther modified with an anionic acrylic latex and/or a water soluble polymer having a weight average molecular weight froni 100,000 - 2,000,000. It is asserted that the tensile strengths of glass mats foimed with the modified urea-formaldehyde resin possess superior tear strength and improved tensile strengths.

U.S. Patent Nos. 5,914,365 and 6,084,021 to Chang et al. describe an aqueous binder composition that contains a urea-formaldehyde resin modified with a water-soluble styrene-maleic anhydride copolymer (SMA). The binder composition is used in the preparation of fiber mats which may be used as substrates in the manufacture of roofing shingles atid composite flooring. It is asserted that glass fiber mats made using the binder coinpositions exhibit eiihanced wet tensile strength, wet mat strength, diy tensile strength, and tear strength.

U.S. Patent No. 5,851,933 to Swartz et al. disclose methods for making non-woven fibrous mats that produce superior tear strengths in roofing products. The mats are foi7ned by a wet-laid process in which the applied binder contains an aqueous urea-foi7naldehyde resin and a self-crossliiiking copolymer of a vinyl aciylic or polyvinyl acetate.

U.S. Patent Nos. 5,445,878, 5,518,586, and 5,656,366 to Mirous describe a urea-foi7naldehyde resin modified with a water-insoluble anionic phosphate ester.
Glass fiber mats formed using the modified urea-formaldehyde resin as a binder and a liydroayetllyl cellulose-containing wliite water glass slui-iy is asserted to exhibit high tear strengtlis.
U.S. Patent No. 4,430,158 to Jackey et al. discloses a method of improving the wet tensile strength of sized glass fiber mats by applying a binder composition that contains a urea-foi7naldehyde resin and 0.01 - 5% by weight of a surfactant that is highly soluble and capable of wetting the surfaces of the sized glass fibers. The su.rfactant is preferably an ionic surfactant such as a sodium dodecylbenzene sulfonate.

U.S. Patent Publication No. 2005/0070136 to Shoemake et al. describes a thermosetting urea-forinaldehyde resin modified with a binding-eiihancing amount of a protein useful as a binder in the formation of glass fiber mats. Preferably the protein is a vegetable protein, and even more preferably, a soy protein. The glass mats are asserted to demonstrate wet tensile strengths, tear strengths, and diy tensile strengths substantially equivalent to urea-foimaldehyde resin binders modified with synthetic additives.

Despite these disclosures, there exists a need in the art for new binder compositions for fiber mats that provide even f-urther improvements in mat tensile and/or tear strength properlies.

SUMMARY OF THE INVENTION
It is an object of the present invention to provide a two-part binder composition formed of a binder pre-mix and at least one coupling agent. The choice of binder forming the binder pre-mix is not particularly limited, and may include a modified urea-formaldehyde binder, a non-modified urea-formaldehyde binder, foi7naldehyde-fi=ee binders, and combinations thereof. In addition, the binders may formed as a"one-part package" in which the binder is pre-mixed with a modifying agent and packaged as a one component system or a"two-part package" in which the binder and the modifying agent are not pre-mixed. In a prefeiTed embodiment, the binder is a standard urea-formaldehyde binder modified with a styrene butadiene rubber latex modifier. Suitable examples of coupling agents for use in the inventive binder composition include silane coupling agents and reactive siloxanes. In prefeiTed embodiments, the coupling agent is an aminosilane coupling agent. A weak organic acid may be added to the binder composition to hydrolyze the silane coupling agent.

It is also an object of the present invention to provide a chopped strand mat for use in roofing applications that has improved hot wet tensile strength. The chopped strand may be foixned of a plurality of glass fibers held together in a sheet foi7n by a two-part binder composition. The glass fibers used to form the chopped strand glass mats may be any type of glass fiber, such as A-type glass fibers, C-type glass fibers, E-type glass fibers, S-type glass fibers, E-CR-type glass fibers (for exaMple, Advantex'RD glass fibers comniercially available from Owens Corning), wool glass fibers, or combinations thereof.
Optionally, other reinforcing fibers such as mineral fibers, carbon fibers, ceramic fibers, natural fibers, and/or synthetic fibers may present in the chopped strand mat in addition to the glass fibers. The binder is preferably the two-part binder composition described above.
It is a further object of the present invention to provide a method of making a chopped strand glass mat that has improved hot wet tensile strengths in which a coupling agent is added to the chopped strand mat via the binder in a wet-laid mat processing line.
Chopped glass fibers are added to white water containing various surfactants, viscosity modifiers, defoaniing agents, and/or other chemical agents with agitation to foim a glass fiber sluny. The slurry is deposited onto a moving foi7ning wire or foraminous conveyor to form a web of intermeshed fibers. Water is removed, such as by a vacuum system, and a binder containing at least one coupling agent is applied to the web of fibers. The binder-coated web is passed tllrough a diying oven to remove any of the water remaining in the web, cure the binder, and form the chopped strand glass mat. The binder is preferably the two-part binder composition described above.
It is yet another object of the present invention to provide a method of making a chopped strand glass mat that has improved hot wet tensile strengths in wluch a coupling agent (or coupling agents) is separately added to the web of chopped fibers during the forniation of the chopped strand mat in a wet-laid mat processing line.
Chopped glass fibers are added to white water containing various surfactants, viscosity modifiers, defoaming agents, and/or other chemical agents with agitation to foiin a glass fiber slui7y.
The sluriy is deposited onto a moving forming wire or foraminous conveyor to form a web of intermeshed fibers. Water is removed from the web by conventional vacuum or air suction system. A binder is applied to the web by a binder applicator. The binder utilized is not particularly limited, and may include any conventional one- or two-part binder compositions known to those of skill the art. A coupling agent is also applied to the surface of the web, either before or after the application of the binder. The coupling agent may be added to the web at any location prior to the web entering the diying oven.
Suitable coupling agents include silane coupling agents and reactive siloxanes. Preferably, the coupling agent is one or more aminosilanes. Once the binder and coupling agent have been applied to the web, the web is passed tluough a diying oven to remove any remaining water and cure the binder composition.

It is another object of the present invention to provide a method of forming a chopped strand mat that has improved hot wet tensile strengths in which a coupling agent is added to the white water in a wet-laid, chopped strand mat processing line.
Suitable coupling agents include silane coupling agents and reactive siloxanes.
Preferably, the coupling agent is one or more aminosilanes. Glass fibers are deposited into the white water containing the coupling agent(s) and any conventionally used surfactants, viscosity modifiers, defoaming agents and/or other suitable chemical agents to form a glass slui7y.
The slurry is deposited onto a foraminous conveyor or wire mesh and a substantial portion of the water is removed, such as by a vacuum system. A binder is applied to the web of fibers, the web is conveyed to a diying oven where the remaining water is removed, and the binder is cured. The binder may be any conventional binder k.nown to those of skill in the art.

It is an advantage of the present invention that chopped strand mats formed according to any embodiment of the present invention as disclosed herein may be formed with fibers treated with a size composition that does or does not include a coupling agent.
As a result, virtually any glass fiber may be utilized in forming the chopped strand glass mats of the present invention.
It is another advantage of the present invention that the two-part binder composition of the present invention may utilized in a chopped strand mat forming process without having to change process parameters or modi~7 the equipment on existing wet-laid mat processing lines.

It is yet another advantage of the present invention that the application or inclusion of at least one coupling agent to the chopped strand mat during a wet-laid mat forming process improves the hot wet tensile strengths of the chopped strand mats.

It is a fi,trther advantage of the present that the inclusion of a coupling agent or agents to the chopped strand mat during the wet-laid process results in an improvement in the dty tensile strength of the formed shingles. As a result, perrnit manufacturers can run their shingle production lines at a faster rate with less tearing or "break up" of the shingles and increase productivity may be achieved by.

The foregoing and other objects, features, and advantages of the invention will appear more fully hereinafter from a consideration of the detailed description that follows.
It is to be expressly understood, however, that the drawings are for illustrative purposes and are not to be constiued as defining the limits of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages of this invention will be apparent upon consideration of the ?5 following detailed disclosure of the invention, especially when taken in conjtuiction with the accompairying drawings wherein:

FIG. I is a schematic illustration of a wet-laid processing line for fonning a chopped strand mat utilizing a two-part binder composition according to at least one exemplary embodiment of the present invention; and FIG. 2 is a schematic illustration of a wet-laid processing line for fomiing a chopped strand mat depicting the application of a coupling agent to a web according to at least one exemplary embodiment of the present invention.

DETAILED DESCRIPTION AND
PREFERRED EMBODIMENTS OF THE INVENTION
Unless defined otherwise, all technical and scientific terms used herein have the sanie meaning as conunonly understood by one of ordinaiy skill in the art to which the invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are described herein. All references cited herein, including published or coiTesponding U.S. or foreign patent applications, issued U.S. or foreign patents, or any other references, are each incorporated by reference in their entireties, including all data, tables, figures, and text presented in the cited references.
In the drawings, the thiclcness of the lines, layers, and regions may be exaggerated for clarity. It is to be noted that like numbers found throughout the figures denote like elements. It will be understood that when an element is refeiTed to as being "on," another element, it can be directly on or against the other element or intervening elements may be present. It is also to be understood that the term "web" and "mat" may be used interchangeably herein.

The present invention relates to non-woven, wet-laid chopped strand glass mats for use in roofing applications that have improved hot wet tensile strengths. The present invention is predicated, at least in part, on the discoveiy that improved hot wet tensile strengths in chopped strand mats may be obtained by the application or inclusion of at least one coupling agent to the chopped strand mat during a wet-laid mat foiming process.
Conventionally, a coupling agent has been added to the size forinulation applied to the glass fibers during the forination of the glass fiber.
The glass fibers used to form the chopped strand glass mats may be any type of glass fiber, such as A-type glass fibers, C-type glass fibers, E-type glass fibers, S-type glass fibers, E-CR-type glass fibers (fof- exairaple, Advantex glass fibers conunercially available from Owens Corning), wool glass fibers, or combinations thereof. In at least one preferred embodiment, the glass fibers are wet use chopped strand glass fibers (WUCS).

Wet use chopped strand glass fibers may be fonned by conventional processes known in the ai-t. It is desirable that the wet use chopped strand glass fibers have a moisture content of from 5 - 300/'o, and even more desirably a moisture content of fi=om 5 -15%.

The use of other reinforcing fibers such as mineral fibers, carbon fibers, ceramic fibers, natural fibers, and/or synthetic fibers such as polyester, polyethylene, polyethylene terephthalate, polyolefin, and/or polypropylene fibers in the chopped strand glass mat is considered to be within the purview of the invention. As used herein, the tei7n "natural fiber" is meant to indicate plant fibers extracted from any part of a plant, including, but not limited to, the stem, seeds, leaves, roots, or bast. The term "synthetic fibers" as used herein is meant to indicate any man-made fiber having suitable reinforcing characteristics.
However, it is prefeiTed that all of the fibers in the chopped strand mat are glass fibers.
The glass fibers may be foi-ined by conventional methods l:nown to those of skill in the art. For example, the glass fibers may be fonned by attenuating streams of a molten glass material from a bushing or orifice. The attenuated glass fibers may have diaineters of about 5 - 30 microns, preferably fi-om 10 - 20 microns. After the glass fibers are drawn from the bushing, an aqueous sizing composition is applied to the fibers. The sizing may be applied by conventional methods such as by an application roller or by spraying the size directly onto the fibers. The size protects the glass fibers from breakage during subsequent processing, helps to retard interfilament abrasion, and ensures the integrity of the strands of glass fibers, for example, the intercoiuiection of the glass filaments that foi7n the strand.
The size composition applied to the glass fibers typically includes one or more film forming agents (such as a polyvinyl alcohol film foi-rner, cellulose film foimer, polytu=ethane film fonner, a polyester film former, and/or an epoxy resin film former), at least one lubricant, and at least one silane coupling agent (such as an aminosilane or methacryloxy silane coupling agent). The coupling agent chemically interacts with the glass fibers to couple the glass fibers with a binder or polymer matrix. When needed, a weak acid such as acetic acid, boric acid, metaboric acid, succinic acid, citric acid, fonnic acid, and/or polyaciylic acids may be added to the size composition to assist in the hydrolysis of the silane coupling agent. The size composition may be applied to the glass fibers with a Loss on Ignition (LOI) of approximately 0.05 - 2.0% on the dried fiber. LOI
may be defined as the percentage of orgaiiic solid matter that remains on the glass fiber surfaces after heating them to a temperature sufficient to burn or pyrolyze the organic size from the fibers.
The inclusion of a coupling agent in the size composition requires that the sized fiber be aged a predetermined period of time to permit the coupling agent to react with the fiber so that the cotipling agent is not washed away froni the fiber in the white water slut7y of a wet-laid mat fonning process such as is described in detail below. It is hypothesized that by removing the coupling agent fi-om the sizing composition applied to the glass fibers during fiber formation and applying or incozporating a coupling agent or agents to the chopped strand mat in the mat foi7ning line, the need to age the glass fibers prior to formation into a chopped strand mat may be reduced or eliminated. It is believed that the elimination of the coupling agent the size composition will result in fibers having improved stability and a longer shelf life. In addition, it is believed that fibers sized with a size that does not include a coupling agent would have the ability to be iirunediately utilized in a wet-laid process (for exanzple, directly from a glass forming line), which would decrease the total manufacturing time for the production of chopped strand mats and roofing shingles.

It is further hypothesized that by removing the coupling agent from the sizing coniposition, the negative impact caused by chemical interactions between the coupling agent and the other chemicals in the size composition (for exafnple, lubricants and dispersants) will be eliminated and the efficiency of the remaining chemicals in the size will be increased. In particular, because there is little to no reaction with the lubricants in the size composition, it is believed that product dispersion performance will be improved.

In conventional size compositions, the coupling agents react with the glass fibers.
Occasionally, the coupling agent is highly reactive (such as aminosilane A-1100 from GE
Silicones) and reacts with more than one glass fiber simultaneously. This inter-reaction between the glass fibers may cause a "clumping" or interconnection of the glass fibers. By removing the coupling agent froin the size composition, there is no active agent remaining within the size composition to react with the glass fibers and cause such undesirable "clumping". Therefore, a problem that was caused by the coupling agent in the size (that is, the intercomiection of the glass fibers by the coupling agent) is eliminated by the present invention.

After the fibers are treated with the sizing composition, they may be chopped and packaged in their wet condition as wet use chopped strand glass (WUCS) and processed into a wet-laid chopped strand mat as described below. It is to be appreciated that the chopped strand mats fotmed according to any embodiment of the present invention as disclosed herein may be forined with fibers treated with a size composition that does or does not include a coupling agent. This is an advantageous feature in that unlike conventional wet-laid processes, virtually any glass fiber may be utilized in forming the chopped strand glass mats of the present invention. The cliopped glass fibers may have a length of 0.5 - 2.0 inches. Preferably, the chopped glass fibers have a length of 1-1.5 inches.

In one embodiment of the invention, the coupling agent (or agents) is added to the chopped strand mat as part of a two-part binder composition. In particular, the chopped strand mat is fornied of a plurality of glass fibers held together in a sheet form by a two-part binder composition that includes a binder pre-mix and a coupling agent or a coupling agent package that contains two or more coupling agents.

An exemplaiy process of forming the chopped strand mat utilizing the inventive two-part binder composition is illustrated in FIG. 1. Chopped glass fibers 10 may be provided to a conveying apparatus such as a conveyor 12 by a storage container 14 for conveyance to a mixing tanlc 16 that contains various surfactants, viscosity modifiers, defoaming agents, and/or other chemical agents with agitation to disperse the fibers and fonn a chopped glass fiber slurry (not shown). The glass fiber sluny may be transfei7=ed to a head box 18 where the slui7y is deposited onto a conveying apparatus such as a moving screen or foraminous conveyor 20 and a substantial portion of the water from the sluny is removed to form a fibrous web (mat) of intermeshed fibers 22. The water may be removed from the web (mat) 22 by a conventional vacuum or air suction system (not shown). A
two-part binder composition 24 according to the present invention is then applied to the web by a binder applicator 26. The binder-coated web 28 is then passed through a diying oven 30 to remove any remaining water and cure the binder composition 24. The cured binder 24 provides integrity to the glass mat 32. The foimed non-woven chopped strand mat 32 that emerges from the oven 30 is formed of randomly dispersed glass fiber filaments. The non-woven chopped strand mat 32 may be rolled onto a take-up roll 34 for storage for later use as illustrated.

The two-part binder composition of the present invention may utilized in a chopped strand mat forining process without having to change process parameters such as oven drying time, conveyor speed, etc. In addition, the inventive binder composition may be applied to the chopped strand mat in conventional wet-laid mat manufacturing lines without a modification of the existing equipment.

The two-part binder composition is fornzed of a binder pre-mix and a coupling agent or a coupling agent package containing two or more coupling agents. The binder pre-mix may include a modified or non-modified formaldehyde binder (for exararple a phenol-formaldeliyde binder), a modified urea-formaldehyde binder (for exaiyrple, modified with latex, styrene butadiene latex, a styrene/maleic anhydride copolymer, polyvinyl acetate, a vinyl aciylic copolymer, melainine, or melamine derivatives), a non-modified urea-foi7naldehyde binder, formaldehyde-free binders such as an aciylic binder, a styrene aciylonitrile binder, a styrene butadiene ilibber binder, polyvinyl acetate binders, vinyl aciylic binders, polyurethane binders, and combinations thereof. In addition, the binders may formed as a"one-part package" in which the binder is pre-mixed with a modi~7ing agent and packaged as a one component system or a"tNvo-part package"
in which the binder and the modifying agent are not pre-mixed. In a prefeiTed embodiment, the binder is a standard urea-formaldehyde binder modified with a styrene butadiene rubber latex modifier such as DL 490NA (available con~unercially from Dow Reichhold).

Examples of suitable binders for use in the binder pre-mix of the present invention include Bordon FG 472 (a urea-foitinaldehyde resin binder coinmercially available from Bordon Chemical Co.), GP ' -2984 (a modified urea-formaldehyde resin binder available from Georgia-Pacific), GP O-2948 (a modified urea-foi7naldehyde resin binder available from Georgia-Pacifc), and GP -2928 (a modified tuea-foi-rnaldehyde resin binder available from Georgia-Pacific). The binder pre-mix may be present in the binder composition in an amount of 40 - 80% by weight based on the active solids in the binder composition, and preferably from 55 - 70% by weight based on the active solids in the binder composition.

The inventive binder composition also includes at least one coupling agent. It is to be appreciated that the coupling agents described below may be utilized in any of the embodiments described herein. Aiiy suitable coupling agent identified by one of skill in the art may be utilized in the instant invention. The coupling agent or coupling agent package may be present in the binder composition in an ainount of 0.02 - 5.0%
by weight based on the active solids in the binder composition, preferably in an amount of 0.1 - 1.0 % by weiglit of the active solids in the binder composition, even more preferably 0.1 -0.5% by weight of the active solids in the binder composition, and most preferably 0.2 -0.5% by weight of the active solids in the binder composition.

Preferably, at least one of the coupling agents is a silane coupling agent.
Examples of silane coupling agents which may be used in the present size coniposition may be characterized by the fiinctional groups amino, epoxy, vinyl, methaciyloxy, azido, ureido, and isocyanato. Suitable silane coupling agents include, but are not limited to, aminosilanes, silane esters, vinyl silanes, methaciyloxy silanes, epoxy silanes, sulfiir silanes, ureido silanes, and isocyanato silanes. Specific non-lirniting examples of silane coupling agents for use in the instant invention include y-aminopropyltriethoxysilane (A-1100), n-phenyl-y-aminopropyltrim.ethoxysilane (Y-9669), n-trimethoxy-silyl-propyl-ethylene-diamine (A- 1120), methyl-trichlorosilane (A- 154), Y-chloropropyl-trimethoxy-silane (A-143), vinyl-triacetoxy silane (A-188), methyltrimethoxysilane (A-1630). Other examples of suitable silane coupling agents for are set forth in Table 1. All of the silane coupling agents identified above and in Table 1 are available conunercially from GE
Silicones.

Silanes Label Formula Silane Esters octyltriethoxysilane A-137 CH3(CH2)7(Si(OCH-2CH3)3 methyltriethoxysilane A-162 CH3Si(OCHzCH3)3 methyltrunethoxvsilane A-163 CH3Si(OCH3)3 proprietary A-1230 roprietaiy tris-[3-(trimethoYysilyl) Y-propyl] isocyanurate 11597 Vinyl Silanes proprietai-y RC-1 proprietai-y vinyltriethoxysilane A-151 CH2=CHSi(OCH2CH3)3 vinylh=imethoxysilane A-171 CH2=CHSi(OCH3)3 vinyl-tris-(2-methoxyethoxy) silane A-172 CHz=CHSi(OCH,)CHZOCH3)3 Methaci lox Silanes y-inethaciyloxypropyl- A-174 CH,=C(CH3)CO2CH2CH2CH~Si(OCH3)3 trimethoxysilane Epoxy Silanes /3-(3,4-epoxycyclohexyl)- Q
ethyltrimethoxysilane A-186 ~_CH2CH2Si(OCH3)3 y-glycidoxypropyltrunethoxy A /O\
silane -187 CH2CHCH2 OCH2CH2CH2Si(OCH3) j Sulfur Silanes y-mercaptopropyltrunethoxy A-189 HSCH,CH-,CHZSi(OCH3)3 silane propi-ietary polysulfidesilane RC-2 proprietary Aniino Silanes y-aminopropyltriethoxysilane A-1101 H2NCH2CH2CH2Si(OCH?CH3)3 aminoalkvl silicone A-1106 (H2NC.H2CH2CH2SiO1.5)õ
modified aminoor anosilane A-1103 ---A-1110 H,,NCHZCH~CH~Si(OCH3)3 amino ro yltrimethoxysilane N /3-(aminoethyl)-y-amino ro yltrimetliowsilane A-1120 H2NCH2CH2NHCH CH,CH,Si(OCH3)3 modified aminoorganosilane A-1126 ---modified aniinosilaue A-112S ---triamiiiofunctional silane A-1130 H2NCH2CH,NHCH,CH,NHCH2CH2CH2Si OCH3)3 bis-(y- A-1 170 HN -CH2CH2CH2 Si(OCH3)3 trimethoxysilylpropyl)amine '-CH2CH2 CH2 Si(OCH 3)3 oganomodified y- CH3SiO[CH3)2SiO],,[CH3SiO],,l[CH3SiO]zSiCH3)3 plydiniethylsiloxane 11343 1 1 NR2 NHIIt'Si(OR')3 plyazamide silatie A-1387 ---Ureido Silanes O
y-ureidopropyltrialkoxysilane A-1160 11 H2XCNHCH2CH~,CH2Si(OCH3 )x(OCH3CH2)3-, ~'- Y- ~
ureidopropyltrimethoxysilane 11542 H2nCHHC3 H6Si(OCHS)3 Isocyanato Silanes y-isocyanatopropyltriethoxy A-1310 O=C=NCH2CH2CH2CH2Si(OCHJ,CH3)3 silane The silane coupling agents used in the present invention may be replaced by alternative coupling agents or mixtures. For exaniple, A-1387 may be replaced by a version in which the methanol solvent is replaced by ethanol. A- 1126, an aminosilane coupling agent including a mixture of approximately 24% by weight diaminosilane modified by a surfactant in a methanol solution (GE Silicones), may be replaced with trimethoxy-silyl-propyl-ethylene-diamine (Z-6020 from Dow Corning). A-1120 or may be substituted by a pre-hydrolyzed version. Z-6020 may be replaced by Z-6137, a pre-hydrolyzed version lacking the alcohol solvent and including 33%
diaminosilane in water at a concentration of 24% solids (commercially available from Dow Corning). I

addition, A-1100 may be replaced by its hydrolyzed form Y-9244, which will reduce or eliminate the ethanol emission.

Vinyl aminosilanes, such as Z-6032 and Z-6224, both conunercially available from Dow Coi7iing, are also useful as coupling agents in the present invention. Z-6032 is a 40%
silane solution in methanol. a specific gravity of 0.9% at 25 C, a refractive index of 1.395 at 25 C, and a viscosity of 2.2 at 25 C. The chemical formula is (CH5O)3-SiCH2CH2CHzNHCH2CH2NHCHZ-O-CH=CH2-HCl and is designated N-2-(vinyl benzylamino)-ethyl-3-anlino propyltrimethoxy silane-monohydrogen chloride. Z-6224 has a specific gravity of 0.88 at 25 C, a refractive index of 1.388 at 25 C and is the neutralized (chloride-free) version of Z-6032.

In addition, the coupling agent may include a functionalized organic substrate (that is, at least one organic functional group bonded to an organic substrate).
Exemplary types of functionalized organic substrates include alcohols, ainines, esters, ethers, hydrocarbons, siloxanes, silazanes, silanes, silanols, lactams, lactones, anhydrides, carbenes, nitrenes, orthoesters, imides, enamines, imines, amides, imides, and olefins. The fiuictionalized organic substrate is capable of interacting and/or reacting with the surface of the glass fibers to provide sufficient coupling or bonding between the glass fibers and the binder material. In particular, one end of the molecule reacts or interacts with the glass surface and the other end of the molecule reacts or interacts with the binder. By choosing one or more suitable functionalized organic substrates for the coupling agent system, desired mechanical properties between the glass fibers and the binder can be obtained.

Another example of compounds useful as coupling agents in the present invention include silicon contaiiiing coupling agents (for exaiizple, silane, silanol, and/or siloxane) tailored or functionalized with an organic polymer. For example, silanes tailored with polyurethane are capable of perfonning coupling agent fiuictions to bond the glass fiber and the binder. Another example includes a silanol tailored or functionalized with a polyamide. It is believed that in this example, if the amine is neutralized, a cationic charge forms on the amine, permitting an ionic bond to form between the amine and the glass fiber. The organic portion of the molecule, that is, the organic polymer, then covalently bonds with the binder.

Reactive siloxanes may also be utilized as coupling agents. Examples of reactive siloxanes include DC-1171, DC-75SF, aiid DC-2-7887, all conlniercially available from Dow Corning. Reactive siloxanes are thought to be linear or branched stiuctures with the following monomeric units (I):

I l I
Si-0-Si-O-Si R4 R5 R6 J n (I>
Rl, R2, R3, R4, R5, and R6 may differ from one monomeric unit to another and may be an alkyl (preferabl), a methyl group) or a hydride. When branched, Rl, R2, R3, R4, R5, and R6 may be formed of one or more monomeric units (I). The reactivity of reactive siloxanes and their ability to act as blocking agents increases with increased number of hydride groups for Rl, R2, R3, R4, R5, and R6.
The binder composition may also contain a trace amount of a weak organic acid such as acetic acid, foi7nic acid, succinic acid, and/or citric acid hydrolyze the silane in the coupling agent. It is prefei7=ed that the organic acid is acetic acid. The organic acid may be present in the binder composition in an amount of from 0.1 - 1.0% by weight of the binder composition, preferably 0.3 - 0.6% by weight of the binder composition.

In addition, the binder composition may optionally contain conventional additives for the improvement of process and product performance such as fire retardants, dyes, oils, fillers, colorants, UV stabilizers, lubricants, wetting agents, surfactants, and/or antistatic agents.

In a second embodiment of the present invention, the coupling agent (or coupling agents) is separately added to the web of chopped fibers during the formation of the chopped strand mat in a wet-laid mat processing line. One eYemplaiy process of separately adding the coupling agent to the chopped strand mat is depicted in FIG. 2.
Chopped glass fibers 10 may be provided to a conveying apparatus such as a conveyor 12 by a storage container 14 for conveyance to a mixing tank 16 that contains various surfactants, viscosity modifiers, defoaming agents, and/or other chemical agents with agitation to,disperse the fibers and foi7n a chopped glass fiber sluriy (not shown). The glass fiber s1u.wTy may be transferred to a head box 18 where the slui7y is deposited onto a conveying apparatus such as a moving screen or foraminous conveyor 20 and a substantial portion of the water from the slui-ly is removed to form a web (mat) 22. The water may be removed fi=om the web 22 by a conventional vacuum or air suction system (not shown).

A binder 24 is applied to the web 22 by a binder applicator 26. The binder utilized is not particularly limited, and may include any conventional one- or two-part binder conzpositions laiown to those of skill the art. A coupling agent 36 may then be applied to the web (mat) 22 by a suitable applicator 38 such as a spray applicator or a curtain coater.
The coupling agent 36 may be added to the fibrous web 22 in an amount up to approximately 1% by weiglit of the mat 22. Ttie coupling agent may be any one or more of the coupling agents described in detail herein. The coupling agent(s) 36 may be in the form of a liquid, a sluny, an emulsion, or a foam. Preferably, the coupling agent 36 is a liquid. Although FIG. 2 depicts the coupling agent 36 being added after the binder 24, the coupling agent 36 may be added prior to the application of the binder 24 (embodiment not illustrated in FIG. 2). In fact, the coupling agent 36 may be added to the web 22 at any location prior to the web 22 entering the oven 30. Once the binder 24 and coupling agent 36 have been applied to the mat 22, the mat 22 is passed tlu=ough a diying oven 30 to remove any remaining water and cure the binder composition 24. The foi7ned non-woven chopped strand mat 32 that emerges from the oven 30 may be rolled onto a take-up roll 34 for storage for later use as illustrated.

In at least one preferred embodiment of the invention, the chopped strand mat depicted in FIGS. 1 and 2 is used to fonn a roofing shingle. To foi7n a roofing shingle, asphalt is applied to the chopped strand mat 32, such as by spraying the asphalt onto one or both sides of the mat or by passing the mat through a bath of molten asphalt to place a layer of asphalt on both sides of the chopped strand mat 32 and fill in the interstices between the individual glass filaments. The hot asphalt-coated mat may then be passed beneath one or more granule applicators which apply protective surface granules to portions of the asphalt-coated mat prior to cutting into the desired shape.
The coated mat is then cut to an appropriate shape and size to form the shingle. It is to be appreciated that the application of asphalt to the glass strand mat 32 may be conducted in-line with a wet-laid mat-foi-niing processing line such as is depicted in FIGS. 1 or 2 or in a separate processing line.

In a third embodiment of the present invention, the coupling agent is added to the white water in a wet-laid, chopped strand mat processing line such as is illustrated in FIG.
1. Thus, the white water (such as may be contained in the mixing tank 16 depicted in FIG.
1) contains the surfactants, viscosity modifiers, defoaming agents, and/or other chemical agents conventionally utilized in the white water as well as one or more of the coupling agents described above. The wliite water containing the glass fibers and coupling agent is agitated to form a glass fiber sluiTy. The coupling agent is deposited onto the glass fibers in the white water and incoiporated into the formed glass mat via the glass fibers. The glass fiber sluL-ty is then deposited onto conveying apparatus such as a wire screen or foraminous conveyor and a binder is applied. The binder is not particularly limited and includes any conventional binder suitable for use in a wet-laid mat forming process. The binder is then cured, such as in an oven, to form the chopped strand mat.
Although the inclusion of a coupling agent or agents to the white water results in the addition of the coupling agent to the chopped strand mat, adding a coupling agent to the white water may be cost-prohibitive due to the large amount of coupling agent that would have to be added to the white water for adhesion onto the glass fibers and the high cost of the coupling agents.

It is to be appreciated that the coupling agent may be added to the chopped strand mat by one or more of the embodiments described above. For example, it may be desirable in some instances to add a coupling agent to the chopped strand mat via the two-part binder composition and to add a coupling agent to the sasne chopped strand mat independent of the binder composition by a separate applicator. Alternatively, it may be desirable to add a coupling agent to the white water and also add a coupling agent via the two-part binder composition. The application or inclusion of a coupling agent (or agents) to a chopped strand mat by any combined embodiments described herein are considered to be within the purview of the invention.

As discussed above, the application or iiiclusion of at least one coupling agent to the chopped strand mat during aNvet-laid mat foi7ning process improves the hot wet tensile strengths of the chopped strand mats. The ability of a shingle to resist water degradation is a desired property if the shingle is to have long teml perfonnance. An estimate of the long ternz perfonnance of shingles is typically detei7nined in the industry by obtaiiiing the hot wet tensile strengths of the chopped strand mats forming the shingles. It is believed that the hot wet tensile strength performance of the chopped strand mat coiTelates to the performance of the shingle. For example, an increase or improvement in the hot wet tensile strength results in an increase or improvement in the long tei~rn perfoimance in the shingle, whereas a decrease in the hot wet tensile strength results in a decrease in the performance of the shingle. Therefore, it is believed that adding a coupling agent(s) to the chopped strand mat during the wet-laid process as in the present invention, which improves the hot wet tensile strength of the chopped strand mat, would result in shingles having inlproved lifetime performance.
Additionally, including at least one coupling agent to the chopped strand mat during the wet-laid mat forming process increases the dzy tensile strength of a shingle formed from that mat. This increase in tensile strength may permit manufacturers to run their production lines at a faster rate with less tearing or "break up" of the chopped strand mats. As a result, an increase in the productivity may be achieved by the inclusion of a coupling agent or agents to the chopped strand mat during the wet-laid process.
Having generally described this invention, a fiirther understanding can be obtained by reference to certain specific examples illustrated below which are provided for puiposes of illustration only and are not intended to be all inclusive or limiting unless otherwise specified.

Examples Example 1: Hot Tensile Strength Retention of Chopped Strand Glass Mats Formed With Two-Part Inventive Binder Compositions Binder compositions set forth in Tables 2 - 6 were prepared in buckets as described generally below. In particular, Control Binder Composition A (Table 2) was prepared by mixing the urea-formaldehyde resin (Bordon FG 472 from Bordon Chemical Co.), the latex binder (DL 490NA from Dow Reichhold), and water.
Binder pre-mixes for inventive Binder Compositions B - E (Tables 3 - 6) were prepared by mixing the urea-foi7naldehyde resin (Bordon FG 472), latex binder (DL
490NA from Dow Reichhold), and water. Acetic acid and water were mixed to forin an acidic solution. Aininosilanes A- 1100 and Y-9669 (GE Silicones) were added to the acidic solutions as designated in Tables 3 - 6 and moderately agitated to permit hydrolyzation. The hydrolyzed aminosilane(s) were then added to the binder pre-mixes with agitation to foi7n Binder Compositions B - E. Once formed, Binder Compositions B
- E were diluted with water to achieve the target mix solids of approximately 50.00%.

Binder Com osition A (Control) Components of Binder Com osition % by wei lit of the active solids Bordon FG 472( ) 69.23 DL 490NA(') 10.87 W ater 19.90 (a) urea-formaldehyde resin (Bordon Chemical Co.) (b) styrene butadiene rubber latex modifier (Dow Reichhold) Binder Composition B
Components of Binder Composition % by wei ht of the active solids Bordon FG 472(a) 69.23 DL 490NA(') 10.87 Water 19.90 A-1100( ) 0.17 Acetic Acid 0.40 (a) urea-formaldehyde resin (Bordon Cheinical Co.) (b) styrene butadiene rubber latex modifier (Dow Reichhold) (c) y-amulopropyltriethosysilane (GE Silicones) Binder Composition C
Components of Binder Composition % by weight of the active solids Bordon FG 472(a 69.23 DL 490NA(') 10.87 Water 19.90 A-1100' ) 0.43 Acetic Acid 0.40 (a) urea-formaldehyde resui (Bordon Chemical Co.) (b) styrene butadiene rubber latex modifier (Dow Reichhold) (c) y-aminopropyltriethoxysilane (GE Silicones) Binder Coin osition D
Coinponents of Binder Composition % by Nveight of the active solids Bordon FG 472~a) 69.23 DL 490NA(b) 10.87 Water 19.90 Y-9669( ) 0.10 Acetic Acid 0.40 (a) urea-forinaldehyde resin (Bordon Cheniical Co.) (b) styrene butadiene rubber latex modifier (Dow Reichhold) (c) n-phenyl- y-aminopropyltrimethoxysilane (GE Silicones) Binder Coni osition E
Coni onents of Binder Composition % by wei lit of the active solids Bordon FG 472(') 69.23 DL 490NA(') 10.87 Water 19.90 A-1100( ) 0.17 Y-9660) 0.10 Acetic Acid 0.40 (a) urea-fornialdehyde resin (Bordon Clieznical Co.) (b) styrene butadiene rubber latex modifier (Dow Reichliold) (c) 7-aminopropyltrietlioxysilane (GE Silicones) (d) n-phenyl- -y-aminopropyltrimethoxysilane (GE Silicones) E-type chopped strand glass fibers sized with a conventional sizing composition containing one or more film forniing agents, at least one lubricant, and at least one coupling agent were foi7iied into chopped strand glass mats on a sheetfoi7ner using Binder Compositions A - E. The chopped strand glass fibers had a length of 7/8 of an inch and a percent moisture of 10.92%. A chopped strand mat using Binder Composition A
(Control) was replicated to confirm the reproducibility of the foiming process and the data for the average of the two tests were used as data in Tables 7 and 8 for Binder Composition A. 2 inch wide test specimens of the chopped strand mats containing Binder Compositions A -E were then evaluated for wet tensile strength on an Instron tensile testing apparatus. Each of the chopped strand mat samples were soaked in 180 F water for 10 minutes prior to testing for wet tensile strength. The test results are set forth in Table 7.

The chopped strand mat saniples using Binder Compositions A - E were then formed into shinglets on an asphalt coating mimic line. The sliinglet samples were tested for tear strength in the cross machine direction (CD) on an Elmendorf tear testing apparatus according to the testing procedures set forth in ASTM D3462. The results are set forth in Table 8.

Chopped Strand Mat Properties Binder ginder Binder Binder Binder Comp. A Comp. B Comp. C Comp. D Comp. E
(Control) LOI (%) 19.05 16.86 17.57 17.98 19.32 Basis Weiglit 2.06 2.05 1.98 1.97 1.97 Dry Tensile Stren h(Ib/2in) (nID) 91.5 85.0 84.0 75.0 83.0 Hot Wet Tensile Stren li (lb/2in) 27.3 42.1 44.8 37.1 41.5 Retention of Stren h%) 29.9 49.5 53.3 49.5 50.0 Change (%) in wet tensile strength 65.6 78.3 65.6 67.2 froin Binder Com . A (Control) Amount of Silane in Binder Comp. 0.00 0.20 0.50 0.20 0.40 (% diy solids basis) Tear Strength Shinglet Binder Binder Binder Binder Binder Comp. A Comp. B Comp. C Comp. D Comp. E
(Control) Tear Strengtli (g) (CD) 994.5 1064 1072 1083 1026 Change ( /o) in tear strength fi=oin 1,0 7.8 8.9 3.2 Binder Comp. A (Control) As shown in Table 7, the chopped strand mats formed with inventive Binder Compositions B - E demonstrated a marked improvement in wet tensile strength over the cutTent state of the art. As discussed above, an estimate of the long terni perforinance of shingles is detei7nined in the industiy by determining the hot wet tensile strength of the chopped strand mats forming the shingles. It is believed that high hot wet tensile strength perfoimaiice of the chopped strand mat is related to better long teim perfoi7nance of the shingle. The results set forth in Table 7 illustrates that the chopped strand mats formed with the inventive binder compositions had outstanding wet tensile strengths compared to the current state of the art (Binder Composition A). Thus, it is believed that shingles formed from chopped strand mats foimed utilizing the inventive binder composition would have improved long teim performance.
In addition, this improvement in the hot wet tensile strengths of the chopped strand mats is achieved without a decrease in the shingle tear strength, as shown in Table S. This result is an unexpected feature since the addition or increase of a coupling agent in a size foi7nulation for chopped glass fibers commonly results in a reduction in the shingle tear strength.

Examnle 2: Hot Tensile Strengths of Chopped Strand Glass Mats and Shinalets Formed With Two-Part Inyentive Binder Comnositions E-type chopped strand glass fibers sized with a conventional sizing composition containing one or more film forming agents, at least one lubricant, and a coupling agent were formed into chopped strand glass mats on a sheetformer using Binder Compositions A, B, and D set fortll in Tables 2, 3, and 5 respectively. The chopped strand glass fibers had a length of 1 1/4 inches and a percent moisture of 13.22%. A chopped strand mat using Binder Composition A (Control) was replicated to confirtn the reproducibility of the forming process and the data for the average of the two tests were used as data in Tables 9 and 10 for Binder Composition A. 2 inch wide test specimens of the chopped strand mats containing Binder Compositions A, B, and D were then evaluated for wet tensile strength on an Instron tensile testing apparatus. Each of the chopped strand mat samples were soaked in 180 F water for 10 minutes prior to testing for wet tensile strength. The test results are set forth in Table 9.

The chopped strand mat samples using Binder Compositions A, B and D were then formed into shinglets on an asphalt coating mimic line. The shinglet saniples were tested for tear strength in the cross machine direction (CD) and machine direction (MD) on an Elmendorf tear testing apparatus according to the testing procedures set forth in ASTM
D3462. The shinglet samples were also tested for dry tensile strength in the machine direction (MD) on an Instron tensile testing apparatus. The results are set forth in Table 10.

Chop ed Strand Mat Properties Binder Binder Binder Comp. A Comp. Comp.
(Control) B D
LOI (%) 18.29 19.04 18.31 Basis Weight 1.89 1.91 1.86 Diy Tensile Stren h(Ib/2ui) (MD) 110.5 112.0 107.0 Hot Wet Tensile Strength (lb/2in) 45.7 57.7 51.6 Retention of Stren h(%) 41.4 51.5 48.2 Cliange (%) ui wet teiisile strength from Binder Comp. A 24.4 16.4 (Control) Amount of Silane in Binder Com .(% diy solids basis) 0.00 0.20 0.20 Teat= Stren li Shin let Binder Binder Binder Comp. A Comp. Comp.
(Control) B D
Tear Stren li O(CD) 1759 1733 1706 Tear Strength ()(MD) 1343 1223 1317 Total Tear Stren IZ 3101 3068 30S4 Clian e(%) in tear stren h from Binder Com . A(Control) -1.1 -0.5 Tensile Stren hO(MD 239 263.0 268.0 Chan e(% ui Tensile Stren li from Binder Com . A (Control) 10.0 12.1 As shown in Tables 9 and 10, the inclusion of a coupling agent in Binder Compositions B and D improved the hot wet tensile retention of the chopped strand mats with little impact on the tear strength. In addition, as illustrated in Table 10, the inclusion of a coupling agent in the inventive binder compositions used in foi7ning the chopped strand mats demonstrated a positive and significant effect on the shingle diy tensile strength (MD) with a minimal and statistically insignificant change in the total tear strength. This improvement in the diy tensile strength will pei7nit manufacturers to run their shingle production lines at a faster rate with less tearing or "break up" of the shingles.
As a result, an increase in productivity may be achieved by the inclusion of a coupling agent or agents to the chopped strand mat during the wet-laid process.

Example 3: Hot Tensile Strengths of Chopped Strand Glass Mats and Shinglets Formed With Two-Part Inventive Binder Compositions E-type chopped strand glass fibers sized with a conventional sizing composition contaiiiing one or more film foiming agents, at least one lubricant, and at least one coupling agent were fonned into chopped strand glass mats on a sheetformer using Binder Coinpositions A, B, and D set forth in Tables 2, 3, and 5 respectively. The chopped strand glass fibers had a length of 1 1/4 inches and a percent moisture of 13.69%. A
chopped strand mat using Binder Composition A (Control) was replicated to confirm the reproducibility of the foi-ining process and the data for the average of the two tests Nvere used as data in Tables 11 aiid 12 for Binder Composition A. Wet tensile strength of the chopped strand mats were deterinined according to the procedure set forth in EYainple 2 above. The test results are set forth in Table 11. Shinglet samples were then formed and tested for tear strength in both the machine direction (MD) and in the cross machine direction (CD) and diy tensile strength as described in Example 2 above. The results are set forth in Table 12.

Chopped Strand Mat Pro erties Binder Binder Binder Couip. A Coinp. Comp.
(Control) B D
LOI %) 18.7 19.65 17.81 Basis Wei lit 1.88 1.80 1.92 Diy Tensile Stren h(lb/2.in) MD) 112.0 105.5 108.0 Hot Wet Tensile Stren h(lb/2in) 57.5 68.3 59.6 Retention of Strength (%) 51.3 65.0 55.1 Cllange (%) in wet tensile sti-ength from Binder Comp. A 26.7 7.4 (Control) Amount of Silane in Binder Com .(% diy solids basis) 0.00 0.20 0.20 Tear Strength Shinglet Binder Binder Binder Coinp. A Coinp. Comp.
(Control) B D
Tear Sh=eno-th (g) (CD) 1801 1715 1839 Tear Strength (g) (NID 1416 1182 1331 Total Tear Strength 3217 3244 3230 Change (%) in tear strength from Buider Comp. A(Control) 0.8 0.4 Tensile Sh=en hO(MD) 221.0 251 239.0 Change (%) in Tensile Strength from Binder Comp. A 13.6 8.1 (Coiih=ol) As shown in Tables 11 and 12, the inclusion of a coupling agent in the inventive binder compositions improved the hot wet tensile retention of the chopped strand mats with little impact (minimal impact) on the tear strength. In addition, as illustrated in Table 12, the inclusion of a coupling agent in Binder Compositions B and D used to foim the chopped strand mats demonstrated a positive improved effect on the shinglet dry tensile strength (MD). As discussed above in Example 2, improvement in the tensile strength of the shingle will permit manufacturers to run their shingle production lines at a faster rate with less tearing or "break up" of the shingles. As a result, an increase in productivity may be achieved by the inclusion of a coupling agent or agents to the chopped strand mat during the wet-laid process.
The invention of this application has been described above both generically and with regard to specific embodiments. Although the invention has been set forth in what is believed to be the preferred embodiments, a wide variety of alternatives known to those of skill in the at-t can be selected within the generic disclosure, including by way of example, using this invention in the process of forming a continuous filatnent mat, a diy laid mat, or any other fibrous mat having a similar binder system. The invention is not otherwise limited, except for the recitation of the claims set forth below.

Claims (38)

1. A method of forming a chopped strand glass mat for use in roofing applications comprising the steps of:

applying at least one coupling agent to a member selected from the group consisting of a fibrous web and glass fibers during a wet-laid mat forming process, said wet-laid mat forming process including:
dispersing chopped glass fibers in an aqueous medium to form a glass fiber slurry;

depositing said glass fiber slurry onto a conveying apparatus to form a fibrous web;

adding a binder to said fibrous web; and curing said binder to form a chopped strand glass mat.

2. The method of claim 1, wherein said applying step comprises adding said at least one coupling agent to said aqueous medium, said at least one coupling agent being deposited on said chopped glass fibers in said aqueous medium.

3. The method of claim 1, wherein said applying step comprises adding said at least one coupling agent to said binder to form a binder composition including said binder and said at least one coupling agent prior to adding said binder to said fibrous web.

4. The method of claim 1, wherein said applying step comprises depositing said at least one coupling agent on said fibrous web prior to said curing step.

5. The method of claim 4, wherein said applying step comprises depositing said at least one coupling agent on said fibrous web prior to adding said binder to said fibrous web.

6. The method of claim 4, wherein said applying step comprises depositing said at least one coupling agent on said fibrous web after adding said binder to said fibrous web.

7. The method of claim 1, wherein said at least one coupling agent is selected from the group consisting of silane coupling agents, functionalized organic substrates, silicon-containing coupling agents functionalized with a polymer, reactive siloxanes and combinations thereof; and wherein said binder composition is selected from the group consisting of a modified formaldehyde binder, a non-modified formaldehyde binder, a modified urea-formaldehyde binder, a non-modified urea-formaldehyde binder, a formaldehyde-free binder and combinations thereof.

8. The method of claim 7, wherein said functionalized organic substrates are selected from the group consisting of alcohols, amines, esters, ethers, hydrocarbons, siloxanes, silazanes, silanes, silanols, lactams, lactones, anhydrides, carbenes, nitrenes, orthoesters, imides, enamines, imines, amides, imides and olefins.

9. The method of claim 1, wherein said chopped strand mat has a dry tensile strength, a hot wet tensile strength and a resultant hot wet tensile retention percentage of said dry tensile strength, and wherein said hot wet tensile retention percentage of said chopped strand mat having said coupling agent is at least five percent greater than an otherwise identical chopped strand mat without said coupling agent.

10. The method of claim 9, wherein said hot wet tensile retention percentage of said chopped strand mat having said coupling agent is greater than fifty percent (50%) and an otherwise identical chopped strand mat without said coupling agent has a hot wet tensile retention percentage of less than fifty percent (50%).

11. The method of claim 10, wherein said step of applying said at least one coupling agent comprises adding said coupling agent to said binder to form a binder composition, said coupling agent being added in an amount of 0.1 - 1.0 % by weight based on the active solids in said binder composition.

12. The method of claim 10, wherein said step of applying said at least one coupling agent comprises adding said coupling agent to said fibrous web in an amount up to 1% by weight of said fibrous web.

13. A two-part binder composition for use in a wet-laid mat forming process for forming a glass mat useful as a reinforcement in roofing applications comprising:
a binder pre-mix including a binder selected from the group consisting of a modified formaldehyde binder, a non-modified formaldehyde binder, a modified urea-formaldehyde binder, a non-modified urea-formaldehyde binder, a formaldehyde-free binder and combinations thereof; and at least one coupling agent.

14. The two-part binder composition according to claim 13, wherein said at least one coupling agent is selected from the group consisting of silane coupling agents, functionalized organic substrates, silicon-containing coupling agents functionalized with a polymer, reactive siloxanes and combinations thereof.

15. The two-part binder composition according to claim 14, wherein said at least one coupling agent is a silane coupling agent selected from the group consisting of aminosilanes, silane esters, vinyl silanes, methacryloxy silanes, epoxy silanes, sulfur silanes, ureido silanes and isocyanato silanes.

16. The two-part binder composition according to claim 14, further comprising at least one organic acid selected from the group consisting of acetic acid, formic acid, succinic acid and citric acid.

17. The two-part binder composition according to claim 14, wherein said binder is a urea-formaldehyde binder modified with a styrene butadiene rubber latex modifier and said at least one coupling agent is at least one aminosilane coupling agent.

18. The two-part binder composition according to claim 13, wherein said modified urea-formaldehyde binder and modified formaldehyde binder are modified with a member selected from the group consisting of latex, styrene butadiene latex, a styrene/maleic anhydride copolymer, poly-vinyl acetate, a vinyl acrylic copolymer, melamine, melamine derivatives and combinations thereof; and wherein said formaldehyde-free binder is selected from a member selected from the group consisting of an acrylic binder, a styrene acrylonitrile binder, a styrene butadiene rubber binder, polyvinyl acetate binders, vinyl acrylic binders, polyurethane binders and combinations thereof.

19. A method of forming a non-woven chopped strand mat for use in roofing applications comprising the steps of:

depositing a glass fiber slurry on a conveying apparatus to form a fibrous web of intermeshed glass fibers;

applying a binder to said fibrous web;

applying at least one coupling agent to said fibrous web; and curing said binder.

20. The method of forming a non-woven chopped strand glass mat according to claim 19, wherein said binder and said at least one coupling agent are applied to said fibrous web simultaneously as a two-part binder composition.

21. The method of forming a non-woven chopped strand glass mat according to claim 19, wherein said step of applying said binder to said fibrous web and said step of applying said at least one coupling agent occur sequentially.

22. The method of forming a non-woven chopped strand glass mat according to claim 21, wherein said step of applying said binder to said fibrous web occurs prior to said step of applying said at least one coupling agent to said fibrous web.

23. The method of forming a non-woven chopped strand glass mat according to claim 21, wherein said step of applying said binder to said fibrous web occurs after said step of applying said at least one coupling agent to said fibrous web.

24. The method of forming a non-woven chopped strand glass mat according to claim 19, further comprising the step of dispersing glass fibers in an aqueous medium to form said glass fiber slurry prior to said depositing step.

25. The method of forming a non-woven chopped strand glass mat according to claim 19, wherein said binder is selected from the group consisting of a modified formaldehyde binder, a non-modified formaldehyde binder, a modified urea-formaldehyde binder, a non-modified urea-formaldehyde binder, a formaldehyde-free binder and combinations thereof;
and wherein said at least one coupling agent is selected from the group consisting of silane coupling agents, functionalized organic substrates, silicon-containing coupling agents functionalized with a polymer, reactive siloxanes, and combinations thereof.

26. A glass mat for use as a reinforcement comprising:
a plurality of glass fibers combined in the form of a sheet; and a binder and at least one coupling agent for bonding together said glass fibers.

27. The non-woven chopped strand glass mat of claim 26, wherein said at least one coupling agent is selected from the group consisting of silane coupling agents, functionalized organic substrates, silicon-containing coupling agents functionalized with a polymer, reactive siloxanes and combinations thereof.

28. The non-woven chopped strand glass mat of claim 27, wherein said at least one coupling agent is a silane coupling agent selected from the group consisting of aminosilanes, silane esters, vinyl silanes, methacryloxy silanes, epoxy silanes, sulfur silanes, ureido silanes and isocyanato silanes.

29. The non-woven chopped strand glass mat of claim 26, wherein said binder is selected from the group consisting of a modified formaldehyde binder, a non-modified formaldehyde binder, a modified urea-formaldehyde binder, a non-modified urea-formaldehyde binder, a formaldehyde-free binder and combinations thereof.

30. The non-woven chopped strand glass mat of claim 26, further comprising reinforcing fibers selected from the group consisting of mineral fibers, carbon fibers, ceramic fibers, natural fibers and synthetic fibers.

31. The non-woven chopped strand glass mat of claim 26, wherein said chopped strand mat has a dry tensile strength, a hot wet tensile strength and a resultant hot wet tensile retention percentage of dry tensile strength, and wherein said hot wet tensile retention percentage of said chopped strand mat having said coupling agent is at least five percent greater than an otherwise identical chopped strand mat without said coupling agent.

32. The non-woven chopped strand glass mat of claim 31, wherein said hot wet tensile retention percentage of said chopped strand mat having said coupling agent is greater than fifty percent (50%) and an otherwise identical chopped strand mat without said coupling agent has a hot wet tensile retention percentage of less than fifty percent (50%).

33. The non-woven chopped strand glass mat of claim 32, wherein said coupling agent is present in said binder composition in an amount of 0.1 - 1.0 % by weight based on the active solids in the binder composition.

34. A method of forming a non-woven chopped strand mat for use in roofing applications comprising the steps of:

incorporating chopped glass fibers into an aqueous medium including at least one coupling agent;

agitating said aqueous medium to disperse said chopped glass fibers within said aqueous medium to form a fibrous slurry and to deposit said at least one coupling agent on said chopped glass fibers;

depositing said fibrous slurry onto a conveying apparatus to form a web of intermeshed said chopped glass fibers;
applying a binder to said web; and curing said binder to form a chopped strand glass mat.

35. The method of claim 34, wherein said at least one coupling agent is selected from the group consisting of silane coupling agents, functionalized organic substrates, silicon-containing coupling agents functionalized with a polymer and reactive siloxanes.

36. The method of claim 35, wherein said coupling agent is a silane coupling agent selected from the group consisting of aminosilanes, silane esters, vinyl silanes, methacryloxy silanes, epoxy silanes, sulfur silanes, ureido silanes and isocyanato silanes.

37. The method of claim 36, wherein said binder is selected from the group consisting of a modified formaldehyde binder, a non-modified formaldehyde binder, modified urea-formaldehyde binder, a non-modified urea-formaldehyde binder, a formaldehyde-free binder and combinations thereof.

38. The method of claim 34, further comprising the step of adding reinforcing fibers selected from the group consisting of mineral fibers, carbon fibers, ceramic fibers, natural fibers and synthetic fibers to said aqueous medium prior to said agitating step.