CA1067226A - Production of glass fiber products - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A binder composition for glass fibers includes an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde condensates, furfural con-densates, furfuryl alcohol condensates and resorcinol-formalde-hyde condensates. Also present is a hydrolyzable silane coupling agent in which the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms; the silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that the hydrolyzable function is not halo when the substituent function is epoxy. Also included is a compound selected from the group consisting of starch, degradation pro-ducts of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benz?l alcohol, and mixtures thereof.
A bonded glass fiber product i disclosed, and also a method for its production which involves forming glass fibers from molten streams of glass, combining the glass fibers with the heat-curable aqueous bind?r composition, consolidating the fibers and binder composition into a loosely-packed mass, and curing the binder in situ. The fibers call be compressed prior to or during curing of the binder composition.

Description

1(~67Z~6 Glass fiber products of the so-called "wool" and "board" type have been known for many years. Such products are made by several different methods, all of which involve collecting a mass of fibers randomly intermeshed with one another, associating a binder with the intermeshed fibers, and curing the binder. The apparent density of the finished product can vary from one pound per cubic foot, or even less, if the binder associated with the mass of intermeshed glass fibers is merely cured, for example, in a suitable oven, to 20 pounds per cubic foot, or even higher, if the mass of intermeshed fibers is suitably compressed during cure of the associated binder.
Over the years, various binders and binder systems have been suggested for wool- and board-glass fiber products.
For example, U. S. Patent No. 2,225,009 suggests a carbon bond formed by applying carbohydrates, starches, oils, waxes and resins to a wool like product~ and then carbonizing by heating to a suitable temperature in the absence of oxygen.
U. S. Patent No. 2,252,157 acknowledges as prior art the use of such materials as asphalt, gypsum, starch, rosin, linseed oil, glue, sodium silicate, pitch and the like, indicating, however, that those prior art binders which were water soluble had proved unsatisfactory when subjected to moisture conditions. This patent then proceeds to disclose "that a fibrous batt having highly superior properties" can be produced by using, as a binder, a small amount of a thermosetting material such as a phenol-formaldehyde, a urea-formaldehyde, or the like condensate.
A review of the more recent patents relating to binders for glass fiber products of the type in question indicates that the art continued to believe that "highly superior properties" could be achieved by using a thermosetting conden-sate, particularly a phenol-formaldehyde condensate, either alone or in combination with an aminoplast, as the resinous component of binders. See, for example, the following U. S.
patents: 3,704,199 (barium hydroxide can be used as a condensing agent for producing resins, and barium sulfate formed upon neutralization is advantageous in binders formulated from the resins; aminoplasts, specifically, melamine, dicyandiamide, urea and thiourea can also be reacted with phenol-formaldehyde 10 condensates to produce modified resins that can be used in binders for the production of glass fiber products); 3,223,668 (binders useful for producing glass fiber products can be formulated from a phenol-formaldehyde condensate and unreacted dlcyandiamide); 3,380,877 (binders useful for producing glass fiber products can be formulated from a phenol-formaldehyde condensate and unreacted urea); and 3,684,467 (binders useful for producing glass fiber products can advantageously be formulated from a resin produced by condensing phenol and formaldehyde in a comparatively high mole ratio, adding 20 dicyandiamide to the reaction mixture and continuing condensa-tion, adding urea to the reaction mixture and continuing the condensation, cooling and neutralizing).
A binder composition useful for producing glass fiber wool- and board-like products is provided according to the instant invention. The binder composition consists essentially of an aqueous dispersion of a resin, a hydrolyzable silane coupling agent or the hydrolysis products of such a silane, and starch, a degradation product of starch, a starch ether or a mixture of starch, degradation products and starch ethers. The 30 resin can be a phenol-formaldehyde condensate, a phenol-amino-plast-formaldehyde condensate, an aminoplast-formaldehyde condensate, a furfural condensate, a furfuryl alcohol condensate or a resorcinol-formaldehyde condensate. The hydrolyzable silane coupling agent is one where the hydrolyzable function is carboxy, halo, NH2 or alkoxy having from 1 to 4 carbon atoms.
The silane must also have a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon-to-carbon double bond. The hydrolyzable function cannot be halo when the substituent function is epoxy. In addition, the binder can contain a free radical inhibitor, a tetraalkoxy silane wherein the alkoxy group has from one to four carbon atoms, or a fire retardant and crosslinking agent selected from the group consisting of boric acid, ammonium borate, ammonium pentaborate, and compounds having the formulas R3BO3 and (RO-)3 P = 0 wherein R is an alkyl group having from one to twelve carbon atoms or an aryl group having from six to twelve carbon atoms, or the starch, starch degradation product or starch ether has been treated in an aqueous system with a m:ineral acid such as phosphoric acid or sulfuric acid.
Numerous compositions, each of which is an aqueous dispersion of a resin, a hydrolyzable silane coupling agent, starch, a degradation product of starch or a starch ether and a free radical inhibitor, a tetraalkoxy silane, boric acid, or a triethoxy phosphate, are subsequently disclosed herein, together with "wet" and "dry" tensile strengths, as subsequently defined, of test pieces made therefrom. Aqueous binder systems can be formulated from these compositions in conventional manners, and the binders can be used, also conventionally, to produce glass fiber products. The binders usually contain, in 10672Z~

addition to the constituents recited above, an ammonium salt of a strong acid, e.g. ammonium sulfate, as a cure accelerator and an oil, e.g. a mineral oil emulsified with stearic acid and ammonium carbonate, as well as ammonium hydroxide, if required to impart stability to the binder.
Therefore, in accordance with this invention, there is provided a method for making a bonded glass fiber product, which method includes the steps of: forming glass fibers from molten streams of qlass; combining the glass fibers with a heat-curable aqueous binder composition, said binder composition consisting essentially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde con-densates, furfural condensates, furfuryl alcohol condensates and resorcinol-formaldehyde condensates; a hydrolyzable silane coup-ling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, N~2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an add~_ion polymerization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that the hydrolyzable function is not halo when the substituent function is epoxy, and a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from 1 to 4 carbon atoms or of benzyl alcohol, and mixtures thereof; consolidating the fibers and heat-curable aqueous binder composition into a loosely packed mass on a foraminous conveyor; and curing the heat-curable binder composition in situ on the glass fiber product.
The invention also provides, in its broader aspects, an ~ _ 4 _ ' . ,.~

advantageous binder composition, and a bonded glass product manu-factured utilizing the binder composition and the method set forth above.
The following Examples illustrate preferred embodiments of the invention. In the Examples, as elsewhere herein, inclu-ding the appended claims, the terms "percent" and "parts" refer to percent and parts by weight, unless otherwise indicated.

EXAMPLE l A mixing tank provided with a propeller-type agitator was charged with 10 parts of water, and the water and subsequently charged ingredients were stirred during the formulation of a binder composition according to the invention. A 0.04 part por-tion of sodium hexametaphosphate and a 0.004 part portion of an aminoalkylsilane* were added to the tank, followed by a 0.07 part portion of ammonium sulfate, a 1.86 part portion of a 50 percent aqueous solution of urea, a 7.46 part portion of a Condensate A**, and a 0.5 part portion of an oil emulsified with a non-ionic sur-factant. Sufficient additional water was added to provide a binder composition of 16 percent solids.
The binder composition produced as described in the pre-ceding paragraph was sprayed into a region through which glass fibers were being projected onto a foraminous conveyor. The fibers were collected in the form of a wool-like mass associated with the binder composition. The relative proportions of binder composition and fibers were such that the binder, after cure thereof, constituted approximately eleven percent of the *The particular aminoalkylsilane used had the formula NH2c2H4NHc3H6Si(-o CH2CH3)3.

**Subsequently identified.

- 4a -lQ672Z6 total product. Cure was accomplished in an oven maintained at a temperature of about 400F. through which the glass fibers and associated binder were passed in a period of about two minutes, and in which the product was compressed sufficiently that the final product was a board-like mass o glass fibers bonded to one another at points of contact by a resite formed by cure of the binder composition, and had an apparent density of about nine pounds per cubic foot, on the average.
The glass fiber product produced as described in the preceding paragraph had substantially the same properties and characteristics as an analogous product made from a binder containing a condensate prepared by the procedure described in U. S. Patent No. 3,684,467, column 8, lines 1-27.
Condensate A was prepared from 363.6 parts 52 percent formaldehyde, 160 parts phenol, 52 parts water, 14.4 parts calcium hydroxide, 48 parts dextrin and 160 parts 50 percent urea solution in water. The condensate was produced in a stainless steel reactor equipped with a propeller-type agitator and an interior, indirect heat transfer coil through which steam or cooling water was circulated, as required, to control temperature. Agitation was used throughout. The phenol and formaldehyde were added to the reactor first, and were heated to 110F., which temperature was maintained for 3~ hours, during which time the calcium hydroxide, as a slurry in the water, was added gradually. The reaction mixture was then heated to 125F.
and maintained at that temperature for a period of one hour counting the time, approximately ten minutes, required to reach 125F. The temperature was then increased to 150F., and that temperature was maintained for a total of 2~ hours. The dextrin was charged two hours a~ter the reaction mixture reached 150F.

At the end of the 2~ hour period at 150F., cooling water was circulated through the indirect heat exchanger to lower the reaction temperature, and the urea solution was added rapidly.
Cooling water was circulated until the condensate reached a temperature of about 80F.
It will be appreciated that it is not practical to investigate all parameters of a binder system by producing and testing glass fiber products as described above in Example 1.
It has been found that such an investigation is not necessary, because the limits can be determined on the basis of bench testing which has been found to correlate well with the results achieved by testing of the type described in Example 1. The bench testing involves preparing tensile test pieces from a mixture of 582 grams of glass spheres and 18 grams (on a dry solids basis) of the binder being investigated. The spheres and the binder are mixed together and the tensile test pieces are molded therefrom and cured in an oven for seven minutes at 425F. All of the test pieces are aged for sixteen hours, and their tensile strength is then determined: "dry" where the aging was under ambient conditions and "wet" where the aging was at 48C. and 100 percent relative humidity.
Binder systems that have been investigated by the bench test des ribed above are identified, and the wet and dry tensile strengths found for each system are presented, in Table I, below. In Table I, the wet strengths reported are averages of 15, while the dry strengths are averages of 3. The silane, in Examples 10, 11 and 12 and in Control 4 and Control 5 was an epoxyalkoxysilane, CH2~-~CH - CH2-O-CH2-CH2-CH -Si(- O ~H3)3.
In all other cases an aminoalkylsilane was used,

2 2 2 NH - CH2 - CH2 - CH2 - Si(-O CH ) ., . ~. 4 10~7226 TABLE I

Control Bindex Composition or Resin Starch Example ~y~_ Amount ~Ye~ AmountSilane U _ Control 1 B* 29.3g - - 0.4g Example 2 B 26.3g 1* 1.8g 0.4g Example 3 B 26.3g 2* 8.0g 0.4g Example 4 B 26.3g 3* 8.lg 0.4g Example 5 B 21.lg 3 16.4g 0.4g Example 6 B 21.lg 2 16.0g 0.4g Control 2 B 23.4g - - 0.4g 3.6g Example 7 B 21.1g 3 8.1 0.4g 3.6g Example 8 B~ 21.lg 2 8.0 0.4g 3.6g Control 3 C* 24g - - 0.2g Example 9 C 20g 4* lOg 0.2g Control 4 D* 31g - - 0.4g Example 10 D 31g 5* 2.5g 0.4g Example 11 E* 18.7g 0.5 2.5g 0.4g 7.6g ( E20.4g Control 5~ - 0.4g 5.4g ( F*3.4g ( E20.4g Example 12( 5 1.8g ( F3.4g Control 6 B26.3g 2 8.0g - -Example 12** B 24.9g 2 16.0g 0.4g Example 13 B26.3g 6 1.8g0.4g Example 14 B26.3g 7 1.8g0.4g Control 7 B26.3g 1 1.8g * Subsequently identified.
** Also contained O.9g tetraethoxysilane.

TABLE
(concluded) Control or Example Dry Wet __ Control 1 848 576 Example 2 848 602 Example 3 648 808 Example 4 880 728 Example 5 668 488 Exàmple 6 672 50A
Control 2 704 272 Example 7 564 . 300 Example 8 512 248 Control 3 640 268 Example 9 788 300 Control 4 1018 572 Example 10 1080 639 Example 11 840 560 ( Control 51 856 524 Example 121 897 744 Control 6 392 40 Example 12 680 454 Example 13 564 565 Example 14 666 587 Control 7 408 36 Condensate B was prepared from 47.2 parts 52 percent formaldehyde, 18.8 parts phenol, 2.0 parts calcium hydroxide, 6.3 parts melamine and 6.0 parts urea. The condensate was produced in a stainless steel reactor equipped with a propeller-type agitator and an interior indirect heat transfer coil to which steam or cooling water was circulated, as required, to control temperature. Agitation was used throughout the period.
The phenol and formaldehyde were stirred together in the reaction vessel and heated to 42C. The calcium hydroxide was added over 10 a 20 minute time period as the temperature increased to 62C.
The reaction was continued until a free formaldehyde content of 13.8 percent was achieved. The melamine was added to the reaction mixture and the temperature maintained at 65C. for 30 minutes. The urea was added and the reaction product cooled to about room temperature; the solids content of the reaction mixture was 61.5 percent.
Condensate C was prepared from 108 parts 52 percent formaldehyde, 245 parts phenol, 40 parts Portland cement, 6.2 parts melamine and 203 parts paraformaldehyde. The 20 condensate was produced in a stainless steel reactor equipped with a propeller-type agitator. Agitation was used throughout.
The phenol and formaldehyde were stirred together in the reaction vessel at a temperature of about 43C. The Portland cement was added to the reaction vessel over a 60 minute period; the temperature increased to about 70C. and was maintained within a range 70 to 75C. at a pH of about 8.7. The reaction mixture was agitated for an additional 40 minute period prior to the addition of the paraformaldehyde. The paraformaldehyde was added over a 30 minute time period. The reaction mixture was agitated 30 for an additional 15 minutes prior to the addition of the , ,...-,~

1~672Z6 melamine. The temperature at the time of the melamine addition was 85C. The reaction mixture was agitated for a 30 minute period and allowed to cool to room temperature.
Condensate D was prepared from 240 parts 50 percent formaldehyde, 60 parts urea, 126 parts melamine, 54 parts diethylene glycol and 128 parts methanol. The condensate was produced in a stainless steel reactor equipped with a propeller-type agitator. Agitation was used throughout.
The formaldehyde, diethylene glycol and methanol were stirred together in the reactor vessel at 40-50C. The tempera-ture of the reaction mixture increased to 70C. The urea was added, and the reaction mixture solubilized and the pH adjusted by addition of triethanolamine to approximately 8Ø The melamine was added and the reaction product cooled to about room temperature.
Condensate E was prepared from 110.2 parts 50 percent formaldehyde and 94 parts phenol. The condensate was produced in a stainless steel reactor equipped with a propeller-type agitator. Agitation was used throughout. The formaldehyde and phenol were stirred together in the reactor at about 43C.
Barium monohydrate was added and the mixture agitated for sixty minutes. The temperature increased to 60C. and the reaction was allowed to proceed until the free formaldehyde was about 6 to 6~ percent. The reaction mixture was cooled to 35C. and neutralized with 20 percent sulfuric acid to a pH of about 7.2.
Condensate F was prepared from 125.6 parts 52 percent formaldehyde, 60 parts urea, 5.7 parts melamine and 10.8 parts diethylene glycol. The condensate was produced in a stainless steel reactor equipped with a propeller-type agitator. Agitation was used throughout. The formaldehyde and 34.8 parts of the 1()6722f~
urea were stirred together in the reactor at a temperature of about 43C. The reaction mixture wa; solubilized and the pH
adjusted by addition of triethanolamine to approximately 7.1.
The reaction mixture pH was reduced to about 4.6 by the addition of phthalic anhydride, and reaction was ailowed to proceed to a viscosity of about C-Gardner-Holdt at a temperature of about 70C. The rest of the urea, 25.2 parts, was charged. The pH
of the reaction mixture was raised to about 7.9 by addition of triethanolamine. Melamine was added to the reaction mixture and the reaction product cooled to about room temperature.
Type 1 starch is untreated pearl cornstarch. It will be apparent from the nature of the binder composition disclosed herein that other starches such as rice starch, potato starch, and wheat starch are also satisfactory for use in the instant invention.
Type 2 starch refers to starch modified as described below:
A stainless steel pressure reactor having an interior stirrer, cooling coils and a valved steam inlet was charged with 20 1000 grams starch, 800 grams water and 120 grams adipic acid.
The vessel was sealed and stirring of the contents was commenced.
Steam was introduced into the reactor until the pressure increased to 160 pounds per square inch at a temperature of 212 F. Application of steam pressure was continued; the temperature of the reaction mixture increased to 280F. The steam inlet valve was closed. The reactor showed a gradual pressure increase to 240 pounds per square inch, and then increased rapidly to 610 pounds per square inch. Water was then introduced into the cooling coils after the temperature had 30 reached 312 F. at a pressure of 610 pounds per square inch. The 1(~67ZZ6 cooling water caused an immediate pressure drop to occur. After cooling the reactor to 180F., the r~actor was vente~ and the product removed from the reactor vessel. The product was a solution, tan to gray in color having 22.7 percent solids and a viscosity of 25 cps at 23C. The pH of the solution was 3.3.
Type 3 starch refers to a starch modified as described below:
The pressure reactor described above was charged with 1000 grams starch, 1000 grams water and 120 grams adipic acid, and stirred.
Steam was introduced into the reactor, until the pressure increased to about 160 psi. at a tempexature of 300F.
The reactor was cooled and drained. The liquid portion of the reaction mixture was then added to the reactor. Application of steam pressure was continued; the temperature of the reaction mixture increased to 180F. at a pressure of 160 pounds per square inch. The steam inlet valve was closed. The reactor showed a gradual pressure increase to 215 pounds per square inch, and then, increased rapidly over a nine minute period to 610 pounds per square inch at a temperature of 205F. Water was then introduced into the cooling coils, causing an immediate pressure drop to occur. After cooling the reactor to 180F., the reactor was vented and the product removed from the reactor vessei. The product was a solution, tan to gray in color, having 23.3 percent solids content.
Type 4 starch refers to a starch modified as described below:
A 300 gram portion of pearl starch, a 2000 gram portion of water, and a 53.6 gram portion of 85 percent phosphoric acid were mixed together in a reaction vessel; the " . .
~ ~

pH of the mixture was about 1.6. The mixture was agitated at 48C. for about sixteen hours. The product was a solution, tan to gray in color.
Type 5 starch also refers to a starch modified as described below:
A 5 gram portion of benzylated starch was added to 50 grams water, heated to 75C. and held at that temperature for ten minutes. The cooked starch was then cooled to room tempera-ture.
It will be appreciated from the data presented in Table I, above, that starch, starch degradation products and starch ethers can be used in many different aqueous resin systems provided that an appropriate silane is also present. In Examples 3 and 4, 10 percent of the starch degradation products produced by heating pearl cornstarch in an aqueous acid system under pressure actually caused an increase in wet strength (compared to Control 1). In other cases, the data indicate that starch or the like is not detrimental to the wet tensile strength.
This is highly significant, because ik means that inexpensive starch can be substituted for costly resins in binder systems, and without loss of strength.
Phenol formaldehyde condensates, phenol-aminoplast-formaldehyde condensates and aminoplast-formaldehyde condensates are preferred families of binder resins for use in binders according to the invention. Aminoalkylalkoxysilanes are preferably used with phenol-formaldehyde condensates, while aminoalkylalkoxysilanes and alkoxysilanes with a substituent having an epoxy function are preferred families of silanes for use with phenol-aminoplast-formaldehyde condensates and with aminoplast-formaldehyde condensates.

~7ZZ6 Binder systems according to the present invention will ordinarily contain conventional ingredients in addition to the condensate, the silane and the starch, starch degradation product or starch ether. For example, the sodium hexameta-phosphate, the ammonium sulfate and the oil emulsion used in the binder of Example 1 all serve their usual functions, and without interfering with the unexpected cooperation among the recited essential binder ingredients. Such materials will ordinarily be employed in binders according to the invention.

A binder system made up of a Phenol-aminoplast-formaldehyde Condensate A*, a Starch Decomposition Product B*, an Aminoalkylalkoxysilane C** and boric acid was investigated by a bench test which has been found to give a reliable indica-tion of the performance of a binder system in producing glass fiber products. The bench te-Qt involved preparing tensile test pieces from a mixture of 582 grams of glass spheres and 18 grams (on a dry solids basis) of the binder being investigated. The spheres and the binder are mixed together and the tensile test pieces are molded therefrom and cured in an oven for seven minutes at 425F. All of the test pieces are aged for sixteen hours, and their tensile strength is then determined: "dry"
where the aging was under ambient conditions and "wet" where the aging was at 48C. and 100 percent relative humidity.
Tensile test pieces were prepared as described above from 20 grams Phenol-aminoplast-formaldehyde Con-A, 10 grams Starch Decomposition Product B, 0.4 gram Aminoalkylalkoxysilane * Subsequently identified.

** Aminoalkylalkoxysilane C had the formula NH2C2H4NHC3H6si(-o CH3)3-C and 0.6 gram boric acid. The test pieces were found to have a dry tensile strength of 572 pounds per square inch (average of

3) and a wet tensile strength of 504 pounds per square inch (average of 15): 88 percent "retention" where "retention" is the ratio of the wet tensile strength to the dry tensile strength.
For purposes of comparison, but not according to the instant invention, tensile test pieces were prepared as described above from 20 grams Phenol-aminoplast-formaldehyde Condensate A, 10 grams Starch Decomposition Product B and 0.4 gram Aminoalkyl-alkoxysilane C. These test pieces were found to have a dry tensile strength of 788 pounds per square inch (average of 3) and a wet strength of 300 pounds per square inch (average of 15):
38 percent retention. Again for purposes of comparison, test pieces were prepared as described above from 24 grams Phenol-aminoplast-formaldehyde Condensate A and 0.4 grams Aminoalkyl-alkoxysilane C. These test pieces were found to have a dry tensile strength of 640 pounds per square inch (average of 3) and a wet tensile strength of 268 pounds per square inch (average of 15): 42 percent retention.
It has been found that valid comparisons cannot necessarily be made between the absolute values of tensile strength determined by the test described above, because sub-stantial variations occur from time to time in the average tensile strengths deternined for any given system. However, these variations are in both wet and dry tensile strengths; as a consequence, the percent retention is substantially constant for any given system, regardless of variations in the magnitude of the wet and dry tensile strengths. It follows that the comparative data presented above indicates a significant improvement in the binder system of Example 1, by comparison 1~)67Z26 with the same system except that bor:ic acid was omitted, and even by comparison with the same system except that both starch and boric acid were omitted.
Phenol-aminoplast-formaldehyde Condensate A was prepared from 108 parts 52 percent formaldehyde, 245 parts phenol, 40 parts Portland cement, 6.2 parts melamine and 203 parts paraformaldehyde. The condensate was produced in a stainless steel reactor equipped with a propeller-type agitator.
Agitation was used throughout. The phenol and formaldehyde were stirred together in the reaction vessel at a temperature of about 43C. The Portland cement was added to the reaction vessel over a 60 minute period; the temperature increased to about 70C. and was maintained within a range 70 to 75C. at a pH of about 8.7. The reaction mixture was agitated for about 40 minutes after completion of the addition of Portland cement.
The paraformaldehyde was then added over a thirty minute time period. The reaction mixture was agitated for an additional fifteen minutes, and the melamine was then added. The temperature at the time of the melam:ine addition was 85C. The reaction mixture was agitated for a thirty minute period and allowed to cool to room temperature.
Starch Decomposition Product B was produced by charging a 300 gram portion of pearl starch, a 2000 gram portion of water, and a 53.6 gram portion of 85 percent phosphoric acid to a reaction vessel; the pH of the mixture was about 1.6. The mixture was agitated at 48C. for about sixteen hours. The product was a solution, tan to gray in color.

A 300 gram portion of Starch Decomposition Product B

was mixed in a beaker with 15 grams propylene oxide, and the resulting solution was allowed to stand for sixteen hours at ambient temperature of about 25C. I'he reaction mixture was then heated for eight hours at 48C. and, after cooling to ambient temperature, was used, designated "Starch degradation ether D", as described below.
Tensile test pieces were prepared as described above from 20 grams Phenol-aminoplast-formaldehyde Condensate A, 10 grams Starch degradation ether D, 0.4 gram Aminoalkylalkoxysilane C and 0.6 gram boric acid. The tensile test pieces were found to have a dry tensile strength of 600 pounds per square inch (average of 3) and a wet tensile strength of 468 pounds per square inch (average of 15): 78 percent retention.
Other binder systems which have been investigated by determining wet and dry tensile strengths of test pieces produced therefrom as described above, and the wet and dry tensile strengths (pounds per square inch) and percent retention are presented in Table II below. In each case, the binder was made from 20 grams Phenol-aminoplast-formaldehyde Condensate A, 10 grams Starch Decomposition Product B, 0.4 gram Aminoalkyl-alkoxysilane C and a fourth constituent. The identity of the fourth constituent and the amount used are given in the Table, in addition to the indicated data concerning strength:

1067;~26 o a o ~ ~
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_~
`
S ~
r~
a~
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~1 CO 0~ 11-E~ ~~ ~ ~D

~J
a~
O
O O O
a) ~ c H ¦

*
I O
~ O 1~ ~
m ~ s ~ ~
s ,, a o h ~ h ~a ~ a~ ~ ~1 o ~ a~rl H E~

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r co ~ 5:
r-l ,1 ,_ ll ~1 ~1 ~1 X X X
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~, The triethoxyphosphate additive in Example 18 was used for the purpose of improving flame retardancy and as a crosslinking agent. The data reported above indicate that this compound, when so used, is not detrimental to physical proper-ties.

Tensile test pieces have also been prepared and tested as described above from 24.9 grams of a different phenol-aminoplast-formaldehyde condensate, 16.0 grams of a different starch degradation product, 0.4 gram of Aminoalkylalkoxysilane C
and 0.9 gram tetraethoxysilane. The tensile strength, dry, was found to be 680 pounds per square inch (average of 3), and, wet, 454 pounds per square inch (average of 15).
The specific phenol-aminoplast-formaldehyde condensate used in the procedure described in Example 20was prepared from 47.2 parts 52 percent formaldehyde, 18.8 parts phenol, 2.0 parts calcium hydroxide, 6.3 parts melamine and 6.0 parts urea. The condensate was produced in a stainless steel reactor equipped with a propeller-type agitator and an interior indirect heat transfer coil to which steam or cooling water was circulated, as required, to control temperature. Agitation was used through-out the period. The phenol and formaldehyde were stirred together in the reaction vessel and heated to 42C. The calcium hydroxide was added over a period of 20 minutes as the temperature increased to 62C. The reaction was continued until a free-formaldehyde content of 13.8 percent was achieved. The melamine was added to the reaction mixture and the temperature maintained at 65C. for 30 minutes. The urea was added and the reaction product cooled to about room temperature; the solids 1(~67ZZ6 content of the reaction mixture was 61.5 percent.
The starch degradation product used in the procedure described in Example20 was produced in a stainless steel pressure reactor having an interior stirrer, cooling coils and a valved steam inlet. The reactor was charged with 1000 grams pearl corn starch, 800 grams water and 120 grams adipic acid.
The vessel was sealed and stirring of the contents was commenced.
Steam was introduced into the reactor until the pressure increased to 160 pounds per square inch at a temperature of 212F. Application of steam pressure was continued; the temperature of the reaction mixture increased to 280F. The steam inlet valve was closed. The reactor pressure showed a gradual increase to 240 pounds per square inch, and then increased rapidly to 610 pounds per square inch. Water was then introduced into the cooling coils after the temperature had reached 312F. at a pressure of 610 pounds per square inch. The cooling water caused an immediate pressure drop to occur. After cooling to 180F., the reactor was vented and the product removed from the reactor vessel. The product was a solution, tan to gray in color, having 22.7 percent solids and a viscosity of 25 cps. at 23C. The pH of the solution was 3.3.
It has been found that starch, compounds which are degradation products of starch and starch ethers can all be used in various types of binder systems useful in producing glass fiber products provided that an appropriate silane, or the hydrolysis products thereof, is included in the binder system. This result is unexpected in view of the extremely detrimental nature of starch and the like, as previously used, in binder systems which did not contain an appropriate silane.
The data presented in the foregoing Examples demonstrates the ~ C

10~i7Z26 added benefit of using from 0.5 to 5 percent of a free radical inhibitor in such a binder, of using from 1 percent to 10 percent of a tetraalkoxysilane wherein the alkoxy group has from 1 to 4 carbon atoms, of using boric acid, ammonium borate, ammonium pentaborate, or a compound having the formula R3B03 or the formula (R0)3 P = 0 whereir. R is an alkyl group having from 1 to 12 carbon atoms or an aryl group having from 6 to 12 carbon atoms and of using a starch, a degradation product of starch, or a starch ether of an alkyl alcohol having from 1 to

4 carbon atoms or of benzyl alcohol, which compound has been treated in an aqueous system with from 5 percent to 15 percent of its weight of a mineral acid such as phosphoric acid or of sulfuric acid.
The use of hydroquinone as a free radical inhibitor is specifically disclosed. Other known free radical inhibitors include guaiacol, benzene azoresorcinol, beta-methylumbelli-ferone, o-cresol, p-toluquinone, p-xyloquinone, thymoquinone, 2,6-dichloroquinone, quinone dioxime, thymoquinone monoxime, quinone chlorimide, 2,6-dibromoquinone chlorimide, nitrosothymol, N-p-tolyl-2-hydroxy-3-naphthamide, N phenyl-2-hydroxy-3-naphthamide, o-chlorophenol, phenol, p-benzoquinone, 1-(4-sulfo-naphthylazo)-2-naphthol, 1-(4-sulfo-phenylazo)-2-naphthol, l-(p-tolylazo)-2-naphthol-3,6-disulfonic acid, the dicalcium salt of l-(4-methyl-2-sulfophenylazo)-2-hydroxy-3-naphtholic acid, o-thiocresol, thiophenol, thio-beta-naphthol, 4,4'di-hydroxy diphenyl and 4,4'dihydroxy-3,3'dimethyl diphenyl.
Phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates and aminoplast-formaldehyde condensates are preferred families of binder resins for use in binders according to the invention. Aminoalkylalkoxysilanes are , ~

~067ZZ6 preferably used ~ith phenol-formaldehyde condensates, while aminoalkylalkoxysilanes and alkoxysi].anes with a substituent having an epoxy function are preferred families of silanes for use with phenol-aminoplast-formaldehyde condensates and with aminoplast-formaldehyde condensates. Examples of the indicated preferred silanes are named in U. S. Patent No. 3,684,467.

~ 22 ~

C~

Claims (18)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method of preparing a bonded glass fiber product, which method comprises the steps of:
(a) forming glass fibers from molten streams of glass;
(b) combining the glass fibers with a heat-curable aqueous binder composition, said binder composition consisting essen-tially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde con-densates, furfural condensates, furfuryl alcohol condensates and resorcinol-formaldehyde condensates; a hydrolyzable silane coup-ling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that the hydrolyzable function is not halo when the substituent function is epoxy; and a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from 1 to 4 carbon atoms or of benzyl alcohol, and mixtures thereof;
(c) consolidating the fibers and heat-curable aqueous binder composition into a loosely-packed mass on a foraminous conveyor;
and (d) curing the heat-curable binder composition in situ on the glass fiber product.

2. A method of preparing a bonded glass fiber product, which method comprises the steps of:
(a) forming glass fibers from molten streams of glass;
(b) combining the glass fibers with a heat-curable aqueous binder composition consisting essentially of an aqueous disper-sion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde conden-sates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formaldehyde conden-sates; a hydrolyzable silane coupling agent wherein the hydroly-zable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hy-drolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.5 to 5 percent of a free radical inhibitor;
(c) consolidating the fibers and heat-curable aqueous binder composition into a loosely-packed mass on a foraminous conveyor;
and (d) curing the heat-curable binder composition in situ on the glass fiber product.

3. A method of preparing a bonded glass fiber product, which method comprises the steps of:

(a) forming glass fibers from molten streams of glass;
(b) combining the glass fibers with a heat-curable aqueous binder composition consisting essentially of an aqueous disper-sion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde conden-sates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formaldehyde conden-sates; a hydrolyzable silane coupling agent wherein the hydroly-zable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hy-drolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 1 percent to 10 percent of a tetraalkoxy silane wherein the alkoxy group has from one to four carbon atoms;
(c) consolidating the fibers and heat-curable aqueous binder composition into a loosely-packed mass on a foraminous conveyor;
and (d) curing the heat-curable binder composition in situ on the glass fiber product.

4. A method of preparing a bonded glass fiber product, which method comprises the steps of:
(a) forming glass fibers from molten streams of glass;

(b) combining the glass fibers with a heat-curable aqueous binder composition consisting essentially of an aqueous disper-sion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde conden-sates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formaldehyde conden-sates; a hydrolyzable silane coupling agent wherein the hydroly-zable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hy-drolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.1 to 5 percent of a fire retardant and crosslinking agent having the formula (RO) 3P=O
wherein R is an alkyl group having from one to twelve carbon atoms or an aryl group having from six to twelve carbon atoms;
(c) consolidating the fibers and heat-curable aqueous binder composition into a loosely-packed mass on a foraminous conveyor;
and (d) curing the heat-curable binder composition in situ on the glass fiber product.

5. A method of preparing a bonded glass fiber product, which method comprises the steps of:
(a) forming glass fibers from molten streams of glass;

(b) combining the glass fibers with a heat-curable aqueous binder composition consisting essentially of an aqueous disper-sion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde conden-sates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formaldehyde conden-sates; a hydrolyzable silane coupling agent wherein the hydroly-zable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hy-drolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.1 to 5 percent of a cross-linking agent selected from the group consisting of boric acid, ammonium borate, ammonium pentaborate, and compounds having the formula R3BO3 wherein R is an alkyl group having from one to twelve carbon atoms or an aryl group having from six to twelve carbon atoms;
(c) consolidating the fibers and heat-curable aqueous binder composition into a loosely-packed mass on a foraminous conveyor;
and (d) curing the heat-curable binder composition in situ on the glass fiber product.

6. A method of preparing a bonded glass fiber product, which method comprises the steps of:
(a) forming glass fibers from molten streams of glass;
(b) combining the glass fibers with a heat-curable aqueous binder composition consisting essentially of an aqueous disper-sion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde conden-sates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formaldehyde conden-sates; a hydrolyzable silane coupling agent wherein the hydroly-zable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hy-drolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof, which compound has been treated in an aqueous system with from 5 percent to 15 percent of its weight of phosphoric acid or of sulfuric acid;
(c) consolidating the fibers and heat-curable aqueous binder composition into a loosely-packed mass on a foraminous conveyor;
and (d) curing the heat-curable binder composition in situ on the glass fiber product.

7. A product formed of glass fibers and a cured binder, wherein the glass fibers are bonded together by said cured binder in a random arrangement form a substantially rigid structure and wherein the cured binder results from heating together on the glass fiber surfaces a binder composition consisting essentially of: an aqueous dispersion of resin selected from the group con-sisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorci-nol-formaldehyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that the hydrolyzable function is not halo when the substituent function is epoxy; and a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alcohol, and mixtures thereof.

8. A product formed of glass fibers and a cured binder, wherein the glass fibers are bonded together by said cured binder in a random arrangement to form a substantially rigid structure and wherein the cured binder results from heating together on the glass fiber surfaces a binder consisting essentially of: an aque-ous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formal-dehyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.1 to 5 percent of a cross-linking agent selected from the group consisting of boric acid, ammonium pentaborate, ammonium borate, and compounds having the formula R3BO3 wherein R is an alkyl group having from one to twelve carbon atoms or an aryl group having from six to twelve carbon atoms.

9. A product formed of glass fibers and a cured binder, wherein the glass fibers are bonded together by said cured binder in a random arrangement to form a substantially rigid structure and wherein the cured binder results from heating together on the glass fiber surfaces a binder consisting essentially of: an aque-ous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde condensates, furfural con-densates, furfuryl alcohol condensates and resorcinol-formalde-hyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.1 to 5 percent of a fire retardant and crosslinking agent having the formula (RO) 3P=O
wherein R is an alkyl group having from one to twelve carbon atoms or an aryl group having from six to twelve carbon atoms.

10. A product formed of glass fibers and a cured binder, wherein the glass fibers are bonded together by said cured binder in a random arrangement to form a substantially rigid structure and wherein the cured binder results from heating together on the glass fiber surfaces a binder consisting essentially of: an aque-ous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde condensates, furfural con-densates, furfuryl alcohol condensates and resorcinol-formalde-hyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 1 percent to 10 percent of a tetraalkoxy silane wherein the alkoxy group has from one to four carbon atoms.

11. A product formed of glass fibers and a cured binder, wherein the glass fibers are bonded together by said cured binder in a random arrangement to form a substantially rigid structure and wherein the cured binder results from heating together on the glass fiber surfaces a binder consisting essentially of: an aque-ous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde condensates, furfural con-densates, furfuryl alcohol condensates and resorcinol-formalde-hyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof, which compound has been treated in an aqueous system with from 5 percent to 15 percent of its weight of phosphoric acid or of sulfuric acid.

12. A product formed of glass fibers and a cured binder, wherein the glass fibers are bonded together by said cured binder in a random arrangement to form a substantially rigid structure and wherein the cured binder results from heating together on the glass fiber surfaces a binder consisting essentially of: an aque-ous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formaldehyde condensates, aminoplast-formaldehyde condensates, furfural con-densates, furfuryl alcohol condensates and resorcinol-formalde-hyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.5 to 5 percent of a free radical inhibitor.

13. A binder composition consisting essentially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formalde-hyde condensates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formal-dehyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that the hydrolyzable function is not halo when the substituent func-tion is epoxy; and a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof.

14. A binder composition consisting essentially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formalde-hyde condensates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formal-dehyde condensates, a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-] function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.5 to 5 percent of a free radical inhibitor.

15. A binder composition consisting essentially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast formalde-hyde condensates, aminoplast formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formal-dehyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms, or of benzyl alco-hol, and mixtures thereof, which compound has been treated in an aqueous system with from 5 percent to 15 percent of its weight of phosphoric acid or of sulfuric acid.

16. A binder composition consisting essentially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formalde-hyde condensates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formal-dehyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH 2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymerization function, an aliphatic: carbon to carbon double bond, or the hydrolysis products of such a silane, with the pro-viso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consist-ing of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alcohol, and mixtures thereof; and from 1 percent to 10 percent of a tetraalkoxy silane wherein the alkoxy group has from one to four carbon atoms.

17. A binder composition consisting essentially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formalde-hyde condensates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formal-dehyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymeriza-tion function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alcohol, and mixtures thereof; and from 0.1 to 5 percent of a crosslinking agent selected from the group consisting of boric acid, ammonium borate, ammonium pentaborate, and compounds having the formula R3BO3 wherein R is an alkyl group having from one to twelve atoms or an aryl group having from six to twelve carbon atoms.

18. A binder composition consisting essentially of an aqueous dispersion of a resin selected from the group consisting of phenol-formaldehyde condensates, phenol-aminoplast-formalde-hyde condensates, aminoplast-formaldehyde condensates, furfural condensates, furfuryl alcohol condensates and resorcinol-formal-dehyde condensates; a hydrolyzable silane coupling agent wherein the hydrolyzable function is selected from the group consisting of carboxy, halo, NH2 and alkoxy having from one to four carbon atoms, said silane having a substituent with an epoxy function, an amine function, a halogen function or, as an addition polymer-ization function, an aliphatic carbon to carbon double bond, or the hydrolysis products of such a silane, with the proviso that when the substituent function is epoxy the hydrolyzable function is not halo; a compound selected from the group consisting of starch, degradation products of starch, starch ethers of alkyl alcohols having from one to four carbon atoms or of benzyl alco-hol, and mixtures thereof; and from 0.1 to 5 percent of a fire retardant and crosslinking agent having the formula (RO) 3P=O
wherein R is an alkyl group having from one to twelve carbon atoms or an aryl group having from six to twelve carbon atoms.