Pollution free method of making phenol formaldehyde resole tire cord dip and product

BACKGROUND OF THE INVENTION
The present invvention is directed to a method of making a reaction product containing phenol formaldehyde resole and its use in combination with a vinyl pyridine latex.sup. 2 for tire cord dips. The phenol formaldehyde resole.sup. 1 is made by a process without isolating any of the products. The reaction product is referred to herein as a phenol formaldehyde resin. A cord coated with the dip composition of the present invention is used to reinforce rubber products such as tires.
.sup.1 Resole is used in its generic sense to describe a family of species.
.sup.2 Latex is used in its generic sense to describe a family of species.
Cord dips based upon the use of a blend of resorcinol formaldehyde resole and a vinyl pyridine copolymer latex are very effective and are widely used.
Cord dips based upon trimethylol phenol are also known, see U.S. Pat. Nos. 3,888,805 and 3,930,095 of van Gils and Kalafus. Cord dips utilizing a mixture of phenol formaldehyde resin and resorcinol formaldehyde resin with an aldehyde latex are disclosed in U.S. Pat. No. 2,748,049 of Kalafus.
While the cord dips of the prior art are quite useful and provide good adhesion between cords and rubber, there are certain problems inherent in their use. Resorcinol, for example, is relatively expensive when compared with phenol. In addition there is only one commercial supplier of resorcinol in the U.S., if not the world. Supplies of resorcinol were recently, though not presently, limited. In addition resorcinol formaldehyde resoles are unstable and have a shelf life of only a few days even at low concentration. Vinyl pyridine is expensive. Trimethylol phenol can be obtained at again a relative high price if one can induce a supplier to manufacture the trimethylol phenol. Trimethylol phenol is not presently being manufactured, is unstable, condensing into a resin on room temperature storage and must be refrigerated if storage is contemplated.
In the manufacture of trimethylol phenol, an excess of formaldehyde is added in the first prior art step. The excess is then removed. The disposal of the removed formaldehyde results in a disposal or a water pollution problem. The removal of the formaldehyde also results in a time consuming and expensive process step. Catalyst removal steps of the prior art have involved ion exchange treatment. The same can be said of the salt forming and crystallization steps employed to isolate the trimethylol phenol salts. The purification process involved in isolating the trimethylol phenol generates even more waste product containing phenols and formaldehyde. Phenolic and formaldehyde pollutants are very difficult, if not impossible, to remove by sewage treatment and by the water treatment normally used for drinking water supplies. This often results in off-taste and odor in drinking water. The off-taste and odor is carried over even by distillation of the polluted drinking water supply.
SUMMARY OF THE INVENTION
We have unexpectedly discovered that phenol formaldehyde resole can be made and used in a cord dip without the necessity of isolation and purification of the resole. The products of our process are not adversely affected by the presence of formaldehyde, salts, phenols and other by-products which were discarded by the prior art. Our process eliminates all pollution problems caused by the prior art purification steps. Our process also eliminates the prior art purification steps and the expense incurred thereby. Our process also reduces the demand for expensive resorcinol and expensive vinyl pyridine by replacing them in part with inexpensive phenol and a relatively cheaper latex respectively. Our process also replaces expensive trimethylol phenol with inexpensive phenol formaldehyde resole. In addtion the phenol formaldehyde resoles of the present invention are much more stable than the resorcinol formaldehyde resoles and trimethylol phenol, having a shelf life of about one hundred days.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The process of the present invention for making a cord dip comprises:
a. reacting in the presence of from about 0.01 to 0.8 mole, preferably 0.0375 to 0.15 mole, of a base catalyst,
1. one mole of phenol with
2. from about 1.0 to 4.0 and preferably 1.5 to 3.0 moles of formaldehyde to form a reaction mixture containing a phenol formaldehyde resole and
b. wihout separating the resole from the reaction mixture, adding based on the following ingredients by dry weight
1. a minor amount of a curing agent consisting of resorcinol and/or resorcinol formaldehyde resin and
2. a major amount of an alkaline dispersion of a rubbery vinyl pyridine copolymer.
The base catalyst preferably is selected from the group comprising sodium hydroxide, and potassium hydroxide. Triethylamine, triethanol amine, may also be operable but are not preferred. The type of the basic catalyst is not critical and any of the catalysts known to be useful in the reaction between phenol and formaldehyde to form resoles can be used. The pH after the addition of the base catalyst preferably has a value of 8.0 to 9.5.
The temperature used in forming the phenol formaldehyde resole is not critical and can range from 10.degree. C. to 100.degree. C. The preferred range is 25.degree. C. to 80.degree. C. The problems with the upper range are controlling the reaction and the production of high molecular weight polymer. The problems of low tempratures include long reaction times.
The formaldehyde can be an aqueous solution of formaldehyde or compound of capable yielding formaldehyde such as paraformaldehyde. From 1.5 to 3.0 moles of formaldehyde for each mole of phenol is preferred. Larger amounts of formaldehyde are undesirable and do not improve the adhesion of the dipped cord to rubber.
Water is used in an amount sufficient to provide for the desired dispersion of the rubber or latex particles, for the solution of the phenol formaldehyde resole, for the solution or dispersion of the curing agent and for the proper solids content to get the necessary pick-up of solids on and penetration between the fibers of the dipped cord. The amount of water present can range from 100 to 1100 parts, preferably from 150 to 900 parts per 100 parts of solids.
Curing agents which can be employed in the practice of the present invention include resorcinol and resorcinol formaldehyde resins. The resins include the base catalyzed resoles and the acid catalyzed novolaks. The ratio of formaldehyde to resorcinol in the resoles can range up to a value of 4:1, any ratio down to 0:1 is also operable. In the novolaks it is preferred not to go over a ratio of 1:1.
The dip thus comprises an aqueous dispersion of the rubbery vinyl pyridine copolymer latex, the solution of the phenol formaldehyde resole, and the solution or dispersion of the curing agent.
The weight ratio of the phenol formaldehyde to curing agent has a value of from 6:1 to 1:2 and preferably from 3:1 to 1:1. The resin and curing agent can also be copolymerized but this is not preferred. The ratio (dry) of the vinyl pyridine copolymer to the mixture of phenol formaldehyde resole and curing agent in the dip is from about 100:5 to 100:75 parts by weight, preferably from about 100:10 to 100:35 parts by weight. The ratio of phenol formaldehyde resin to resorcinol or resorcinol formaldehyde resin has a value of 1:2 to 6:1 and preferably 1:1 to 3:1. Sufficient alkaline material is present in the phenolic solution to prevent premature coagulation of the rubbery copolymer and to solubilize the phenol formaldehyde resole.
The type of rubber emulsion or latex preferably used in the tire cord dip bath of this invention is a latex of a copolymer of a vinyl pyridine and a conjugated diolefin having 4 to 6 carbon atoms. The rubber latex comprises an aqueous emulsion or dispersion of a copolymer of 50 to 98 percent by weight of a conjugated diolefin having 4 to 6 carbon atoms, 2 to 40 percent of a vinyl pyridine and 0 to 48 percent of a styrene with the future qualification that the percentages of the three components add up to 100%. Examples of suitable vinyl pyridines are 2-vinyl pyridine, 4-vinyl pyridine, 2-methyl-5-vinyl pyridine and 5-ethyl-2-vinyl pyridine.
In practicing the present invention, it is usually preferred to use an emulsion or latex of a copolymer of from about 60 to 90 percent by weight of 1,3-butadiene, 0 to 32 percent styrene and 3 to 22 percent of 2-vinyl pyridine, with the further qualification that the percentages of the three components add up to 100%. Excellent results are obtained using a latex of a terpolymer of about 70 percent by weight of 1,3-butadiene, 15 percent styrene and 15 percent 2-vinyl pyridine having a total solids content of around 30 to 50 percent by weight. Blends of latices may be used such as a blend of a 1,3-butadiene/2-vinyl pyridine rubbery copolymer latex and a 1,3-butadiene/styrene rubbery copolymer latex or a blend of a 1,3-butadiene/styrene/2-vinyl pyridine rubber copolymer latex and a 1,3-butadiene styrene rubbery copolymer latex so long as the percent by weight ratio of total monomers in the copolymers is within the ranges as specified above. The ratio of the vinyl pyridine latex to styrene butadiene latex preferably has a value of 3:1 to 1:3. The vinyl pyridine content of the blend is preferably at least 3%. The pH of the latices should be similar and the surfactants and stabilizers should be compatible to avoid coagulation on blending or mixing of the latices. The amounts of polymerization ingredients and the polymerization conditions to use are well known to the art. See "Vinyl and Related Polymers," Schildknecht, John Wiley & Sons, Inc., New York, 1952; "Synthetic Rubber," Whitby, Davis & Dunbrook John Wiley & Sons. Inc., New York, 1954; "Emulsion Polymerization,"Bovey, Kolthoff, Medalia and Meehand, Interscience Publishers, Inc., New York, 1955. Emulsions or latices of rubbery vinyl pyridine copolymers for use in cord dips are shown by U.S. Pat. Nos. 2,561,215; 2,615,826 and 3,437,122.
In order to provide data for the tire cord adhesive of this invention, a standard single-cord H-pull test is employed to determine the static adhesion at room temperature and above of the adhesive-coated tire cord to rubber. All the data submitted herein including the examples which follow are based upon identical test conditions, and all test specimens are prepared and tested in the same way generally in accordance with ASTM Designation: D 2138-67.
In order to apply the adhesive dip to the cords in a reliable manner, the cords are fed through the adhesive dip bath containing the rubber and the phenolic composition and into a drying oven where they are dried. In each case the adhesive-coated cords leaving the dip are dried in the oven at from about 300.degree. to 500.degree. F., or at a temperature below the temperature at which the fibers of the cord would lose their tensile strength, for from about 30-300 seconds. The time the cord remains in the dip is about a second or so or at least for a period of time sufficient to allow wetting of the cord and penetration of the fibers of the cord by the adhesive mixture.
The H-adhesion test referred to above measures the static adhesion of the dried adhesive coated fibers to cured rubber.
In each case the rubber test specimens are made from one of the three standard type rubber compositions using the following three recipes:
______________________________________ PARTSSTOCK A BY WEIGHT______________________________________Natural Rubber 50Butadiene-styrene rubbery copolymer 50average 23.5% bound styrene, SBR-1502,emulsion polymerizedHigh abrasion furnace carbon black 35"Endor", activated zinc salt of 0.65pentachloro - thiophenol,peptizing agent, duPont"Circosol" 2XH, napthenic type oil 7.0Sun Oil CompanyZinc Oxide 3.0Stearic Acid 1.0"AgeRite Spar", a mixture of mono-, 1.0di- and tri-styrenated phenols,antioxidant, R. T. Vanderbilt Co., Inc."Picco 100", alkyl aromatic polyindene 2.0resin, reinforcing and processing oil,Pennsylvania Industrial Chemical Corp.Diphenylguanidine 0.5N-Oxydiethylene benzothiazole- 0.92-sulfenamideSulfur (insoluble) 2.6Petroleum oil (in sulfur) 0.65______________________________________ PARTSSTOCK B BY WEIGHT______________________________________Natural Rubber 46.5Butadiene-styrene rubbery copolymer, 38.5average 23.5% bound styrene, SBR-1500,emulsion polymerizedPolybutadiene, solution polymerized 15.0BD, about 93% cis-1,4, Raw MooneyML-4 at 212.degree. F. about 40-50Carbon black, fast extrusion furnace 45.0Hydrated silica, "Hi-Sil" 233, PPG 15.0Industries, Inc."BLE" 25 antioxidant, a high temperature 2.0reaction product of diphenylamine andacetone, Naugatuck Chemical Division ofUniroyalProcessing oil, a blend of highly 5.0aromatic petroleum fractionsZinc oxide 3.0Stearic acid 1.5"Cohedur" RL, a 1:1 mixture of resorcinol 4.7and "Cohedur" A (the pentamethyl ether ofhexamethylol melamine) which is a color-less viscous liquid which liberatesformaldehyde on heating. Naftone, Inc.N-tert-butyl-2-benzothiazole-sulfenamide 1.2"Santocure" NS, Monsanto Chemical Co.Sulfur 3.0______________________________________ PARTSSTOCK C BY WEIGHT______________________________________Natural Rubber (No. 3 Smoked Sheet) 36.50Butadiene-styrene rubbery copolymer, 43.50average 23.5% bound styrene, emulsionpolymerizedPolybutadiene (solution polymerized BD, 20.00about 93% cis-1,4, Raw Mooney ML-4 at212.degree. F. about 40-50)Carbon black, fast extrusion furnace 35.00Carbon black, high abrasion furnace 35.00(high structure)Alkyl aromatic polyindene resin, 4.5reinforcing and processing aid,Picco 100, Pennsylvania IndustrialChemical Corp.Naphthenic oil, Circosol type 2XH, 32.80Sun Oil CompanyZinc Oxide 3.8Stearic Acid 1.5Mixture of mono, di and tristyrenated 1.2phenols, AgeRite Spar, R. T.Vanderbilt Co. Inc. antioxidantBenzothiazyl disulfide, Altax, R. T. 1.2Vanderbilt Co., Inc., acceleratorTetramethyl thiuram monosulfide, active 0.1ingredient Thionex accelerator, E. I.DuPont de Nemours & Co., Inc.Crystex, about 80% insoluble sulfur 3.0& 20% petroleum oil, Stauffer ChemicalCompany______________________________________
In every case the cords to be tested are placed in parallel positions in a multiple-strand mold of the type described in the single cord H-pull adhesion test designated ASTM D-2138-67, the mold is filled with unvulcanized rubber of the above composition, the cords being maintained under a tension of 50 grams each, and the rubber is cured 20 minutes at around 151.degree. C. to the elastic state. Each rubber test specimen is 0.63 cm thick and has a 0.95 cm cord embedment.
After the rubber has been cured, the hot reticulate cured rubber piece is removed from the mold, cooled and H-test specimens are cut from said piece, each specimen consisting of a single cord encased in rubber and having each end embedded in the center of a rubber tab or embedment having a length of 2.54 cm. The specimens are then aged at least 16 hours at room temperature. The force required to separate the cord from the rubber is then determined at room temperature or 121.degree. C. using an INSTRON tester provided with specimen grips at a crosshead speed of 15.2 cm per minute. The force in Newtons required to separate the cord from the rubber is the H-adhesion value.
The resorcinol formaldehyde novolak used in the following examples contained 0.6 moles of formaldehyde per mole of resorcinol. The novolak contains 15% unreacted resorcinol, 421/2% of a compound having the formula R--CH.sub.2 --R where R is resorcinol and 421/2% of a compound having the formula R--CH.sub.2 R--CH.sub.2 --R.

The following examples will serve to illustrate the invention with more particularity to those skilled in the art. In these examples as elsewhere in the specification and claims parts and percentages are by weight (dry) unless otherwise indicated. P represents phenol and F represents formaldehyde and PF represents phenol formaldehyde resin in the present specification.
EXAMPLE I
This example illustrates how the phenol formaldehyde resole of the present invention can be used to replace trimethylolphenol.
Two phenol formaldehyde resoles, labeled Resin No. 1 and 2 in the following table, were prepared. The following table lists the ingredients placed into a reactor and the reaction condition.
______________________________________ Resin Resin No. 1 No. 2______________________________________Recipe.sup.1 (moles) Phenol 1.00 1.00 Formaldehyde 3.00 3.00 Sodium Hydroxide 0.075 0.075 Water 9.36 9.36Reaction temp., .degree. C 80.sup.2 80.sup.2Reaction time, hrs. 1 2Unreacted Formaldehyde.sup.3 7.7% 6.5% pH 8.9 8.8TSC, %.sup.4 45.1 45.5______________________________________ .sup.1 Given in moles of reactants for clarity of presentation. In actual practice, if 90% phenol solution, 37% formaldehyde solution, and 100% sodium hydroxide are used, no additional water is needed. .sup.2 Temperature of the polymerizer bath. .sup.3 Refers to the level of formaldehyde in the final resin. Conversion of formaldehyde ranged between 65-75% resulting in a minimal yield of trimethylol phenol. Following Examples have similar yields. .sup.4 Calculated on the basis of total phenol consumption. Thin layer chromatography showed approximately 1-2% unreacted phenol.
The resins produced above were then incorporated into a series of five cord dips, the recipes of which are set forth below.
______________________________________DIP RECIPES Dip Recipe No.______________________________________Contents (Parts) 1 2 3 4 5______________________________________Vinyl pyridine 100 100 100 100 100latex.sup.1Resin 16.7 15.4 12.5 9.1 7.2Resorcinol 3.3 4.6 7.5 10.9 12.8TSC.sup.2 40% 40% 40% 40% 40%______________________________________ .sup.1 A terpolymer of 70% 1,3-butadiene, 15% styrene and 15% 2-vinyl pyridine having a solids content of 40%. .sup.2 All dips were aged overnight before cutting down to 15% TSC (total solids content) for dipping.
Five additional cord dips were made using the same five recipes set forth above with the single exception that the resin in each case was replaced with trimethylolphenol.
Commercial aromatic polyamide tire cords were dipped in the above described cord dips with the following results.
__________________________________________________________________________ADHESION DATA FOR COMPARISON OFRESIN 1, RESIN 2 AND TRIMETHYLOLPHENOL H-ADHESION, KEVLAR.sup.1 TO STOCK B TRIMETHYLOLPHENOL RESIN 1 RESIN 2__________________________________________________________________________DIP RECIPE RT.sup.2 121.degree. C RT 121.degree. C RT 121.degree. C__________________________________________________________________________1 253 155 278 161 252 1552 263 160 270 161 275 1633 250 159 248 143 260 1514 235 158 237 144 228 1415 227 153 225 150 232 146__________________________________________________________________________ .sup.1 Kevlar is an aromatic polyamide tire cord available from DuPont. .sup.2 RT means room temperature.
EXAMPLE II
This example illustrates the effect that the amount of catalyst, used to form the phenol formaldehyde resole, has on cord adhesion and resole stability.
The following phenol formaldehyde resoles were prepared using the reactants and conditions set forth in the table below.
______________________________________ Resin Resin Resin No. 3 No. 4 No. 5______________________________________Recipe.sup.1 (moles) Phenol 1.00 1.00 1.00 Formaldehyde 3.00 3.00 3.00 Sodium Hydroxide 0.0375 0.075 0.15 Water 9.36 9.36 9.36Reaction temp., .degree. C 80.sup.2 80.sup.2 80.sup.2Reaction time, hrs. 3 1 1Unreacted Formaldehyde.sup.3 8.40% 7.87% 5.65% pH 8.2 9.0 9.2Brookfield Visc., cps 16.5 15.5 44.5Water Tolerance, %.sup.4 10,000+ TSC, %.sup.5 44.5 45.0 48.0______________________________________ .sup.1 Given in moles of reactants for clarity of presentation. In actual practice, if 90% phenol solution, 37% formaldehyde solution, and 100% sodium hydroxide are used, no additional water is needed. .sup.2 Temperature of the polymerizer bath. .sup.3 Refers to the level of formaldehyde in the final resin. Conversion of formaldehyde ranged between 65-75%. .sup.4 Defined as the weight percent of water added before turbidity appears. .sup.5 Calculated on the basis of total phenol consumption.
Thin layer chromatography showed approximately 1-2% unreacted phenol.
Resin No. 3, 4 and 5 were then used to formulate a series of cord dips according to the following recipes.
______________________________________ DIP RECIPE No.CONTENTS 1 2 3______________________________________Vinyl pyridine 100 100 100latex.sup.1Resin 16.7 15.4 12.5Resorcinol 3.3 4.6 7.5TSC.sup.2 40% 40% 40%______________________________________ .sup.1 A terpolymer of 70% 1,3-butadiene, 15% styrene and 15% 2-vinyl pyridine having a solids content of 40%. .sup.2 All dips were aged overnight before cutting down to 15% TSC for dipping.
Commercial aromatic polyamide tire cords were dipped in the above described formulation with the following results.
______________________________________EFFECT OF CATALYST CONCENTRATION OFRESIN ON ADHESION OF KEVLAR TO STOCK B______________________________________RESIN NO.(CATALYST LEVEL)______________________________________DIPRE- 3 (0.0375) 4 (0.075) 5 (0.15)______________________________________CIPE RT 121.degree. C RT 121.degree. C RT 121.degree. C______________________________________1 241 176 276 163 268 1722 286 181 285 169 Dip solidified3 273 168 252 153 Dip solidified______________________________________ The dips made with resin 3 had a shelf life of 5-8 weeks at room temperature compared to about 6-12 weeks for those made with resin 4. This is because of the longer reaction time in the preparation of resin 3 as compared with resin 4 used in these dips. All dips solidified in 2-3 days at 50.degree. C. The dips with resin 5 had a shelf life of less than 2 weeks (two of the three dips actually lasted less than one day).
EXAMPLE III
The preparation of phenol formaldehyde resoles was studied at 50.degree. C., 60.degree. C. and 80.degree. C. Three resin recipes were used (phenol formaldehyde mole ratios of 1:3.25, 1:3.0 and 1:2.5). The reaction times were varied to give approximately the same unreacted formaldehyde level at various reaction temperatures for each of the two recipes. The resins thus prepared were tested for their adhesive quality in Kevlar, aromatic polyamide, dips.
The following table lists the reactor inputs and the reaction conditions used to make the phenol formaldehyde resoles.
__________________________________________________________________________ RESIN NO.__________________________________________________________________________PROPERTY 6 7 8 9 10 11 12__________________________________________________________________________Recipe (moles) Phenol 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Formaldehyde 2.50 2.50 2.50 3.00 3.00 3.00 3.00 Sodium Hydroxide 0.075 0.075 0.075 0.075 0.075 0.075 0.075 Water 7.91 7.91 7.91 9.36 9.36 9.36 9.67Reaction temp., .degree. C. 50 60 80 50 60 80 60Reaction time, hrs. 16 6 1 16 8 1 8Unreacted Formaldehyde 5.67% 5.97% 5.07% 8.00% 7.60% 7.87% 8.67% pH 9.05 9.10 9.0 9.1 9.10 9.0 8.9Brookfield Visc., cps 14.0 14.0 17.5 16.5 13.5 15.5 13.0Water Tolerance, % 400 10,000+ 10,000+ 10,000+TSC, % 49.0 48.8 49.7 44.8 44.5 45.0 43.1__________________________________________________________________________
The resins produced above were then incorporated into a series of three cord dips, the recipes of which are set forth below.
______________________________________CONTENTS DIP RECIPE No.(PARTS) 1 2 3______________________________________Vinyl pyridine 100 100 100latex.sup.1Resin 16.7 15.4 12.5Resorcinol 3.3 4.6 7.5TSC.sup.2 40% 40% 40%______________________________________ .sup.1 A terpolymer of 79% 1,3-butadiene, 15% styrene and 15% 2-vinyl pyridine having a solids content of 40%. .sup.2 All dips were aged overnight before cutting down to 15% TSC (total solids content) for dipping.
Commercial aromatic polyamide tire cords were dipped in the above described cord dips with the following results.
__________________________________________________________________________ROOM TEMPERATURES, H-ADHESION IN NEWTONS OFKEVLAR TO STOCK B__________________________________________________________________________ MOLE RATIO 1:2.50 1:3.00 1:3.25 .THorizBrace. .THorizBrace. RESIN NO. 6 7 8 9 10 11 12DIP RECIPE TEMPATURE 50.degree. C 60.degree. C 80.degree. C 50.degree. C 60.degree. C 80.degree. C 60.degree. C__________________________________________________________________________1 277 265 257 -- -- 276 --2 261 265 248 256 278 285 2803 -- -- -- 243 248 252 266__________________________________________________________________________
The H-adhesion data reported in the above table may be used to elucidate the effect of mole ratio of phenol:formaldehyde on the adhesion of Kevlar to Stock B. It is seen that the initial mole ratio of the reactants (in the range studied) does not affect adhesion significantly when the dip recipe is adjusted to its optimum level. The data also shows that the reaction time and temperature can be adjusted to attain optimum resin properties for good adhesion.
EXAMPLE IV
This example sets forth the results obtained adhering Kevlar cord to various rubber stocks using various cord dip recipes to treat the Kevlar cord.
Three phenol formaldehyde resoles, Resin Nos. 13, 14 and 15 were prepared as set forth below.
______________________________________ RESIN NO. 13 14 15______________________________________Recipe (moles) Phenol 1.00 1.00 1.00 Formaldehyde 3.00 3.00 3.25 Sodium Hydroxide 0.0375 0.075 0.075 Water 9.36 9.36 9.67Reaction temp., .degree. C 80 60 60Reaction time, hrs. 3 8 8Unreacted Formaldehyde 8.40% 7.60% 8.67% ph 8.2 9.10 8.9Brookfield Visc., cps 16.5 13.5 13.0Water Tolerance, % 10,000+ 10,000+TSC, % 44.5 44.5 43.1______________________________________
The resins produced were then incorporated into a series of three cord dips, the recipes of which are set forth below.
______________________________________CONTENTS DIP RECIPE No.(PARTS) 1 2 3______________________________________Vinyl pyridine 100 100 100latex.sup.1Resin 16.7 15.4 12.5Resorcinol 3.3 4.6 7.5TSC.sup.2 40% 40% 40%______________________________________ .sup.1 A terpolymer of 79% 1,3-butadiene, 15% styrene and 15% 2-vinyl pyridine having a solids content of 40%. .sup.2 All dips were aged overnight before cutting down to 15% TSC (total solids content) for dipping.
Commercial aromatic polyamide tire cords were dipped in the above described cord dips with the following results.
__________________________________________________________________________H-ADHESION IN NEWTON OF KEVLAR TO VARIOUS STOCKS__________________________________________________________________________ RESIN No. 13 14 15__________________________________________________________________________STOCK DIP RECIPE RT 121.degree. C RT 121.degree. C RT 121.degree. C__________________________________________________________________________B 1 241 176 -- -- -- -- 2 286 181 278 162 280 165 3 274 168 -- -- -- --C 1 270 155 -- -- -- -- 2 292 165 263 133 254 142 3 258 151 -- -- -- --A 1 204 141 -- -- -- -- 2 217 143 196 107 196 116 3 193 131 -- -- -- --__________________________________________________________________________
EXAMPLE V
This example illustrates the effect of resin/latex ratio using 20, 15 and 10 parts of the resin/100 parts of the latex. Resin 16, the preparation of which is set forth below, was used.
______________________________________ Resin No. 16______________________________________Recipe (moles) Phenol 1.00 Formaldehyde 3.00 Sodium Hydroxide 0.0375 Water 9.36Reaction temp., .degree. C 80Reaction time, hrs. 3Unreacted Formaldehyde 8.40% pH 8.2Brookfield Visc., cps. 16.5Water Tolerance, % TSC, % 44.5______________________________________
The resin produced above was then incorporated into a series of three cord dips, the recipes of which are set forth below.
______________________________________CONTENTS DIP RECIPE No.(PARTS) 1 2 3______________________________________Vinyl pyridine 100 100 100latex.sup.1Resin 16.7 15.4 12.5Resorcinol 3.3 4.6 7.5TSC.sup.2 40% 40% 40%______________________________________ .sup.1 A terpolymer of 79% 1,3-butadiene, 15% styrene and 15% 2-vinyl pyridine having a solids content of 40%. .sup.2 All dips were aged overnight before cutting down to 15% TSC (total solids content) for dipping.
Commercial aromatic polyamide tire cords were dipped in the above described cord dips and incorporated into rubber stocks A, B and C with the following results.
__________________________________________________________________________H-ADHESION IN NEWTON OF KEVLAR TO VARIOUS STOCKS__________________________________________________________________________ RESIN/LATEX ratio__________________________________________________________________________ 20:100 15:100 10:100STOCK DIP RECIPE RT 121.degree. C RT 121.degree. C RT 121.degree. C__________________________________________________________________________B 1 241 176 266 173 281 160 2 286 181 298 184 275 169 3 274 168 257 147 277 165C 1 270 155 263 143 248 124 2 292 165 248 150 249 131 3 258 151 236 118 246 126A 1 204 141 199 131 190 121 2 217 143 196 136 181 105 3 193 131 176 110 180 106__________________________________________________________________________
For Stock B the H-adhesion does not appreciably decrease as the resin/latex ratio decreases. As little as 10 parts of the resin per 100 parts of the latex may, therefore, be used for Kevlar adhesion to Stock B. For Stocks A and C, however, H-adhesion gradually decreases as the resin/latex ratio is decreased. Adhesions at 15 parts resin/100 parts latex are adequate. Thus, while 20 parts resin/100 parts latex is preferred, 15 parts resin/100 parts latex may also be used without significant loss of adhesion to the three stocks.
The advantage in using lower resin/latex ratio lies in increased dip stabilities. At 50.degree. C., the dips solidified in 2-3, 4-8 and 10-20 days for resin levels of 20, 15 and 10 parts per 100 parts of the latex, respectively.
EXAMPLE VI
This example illustrates the effect of aging the cord dip upon subsequent adhesion of rubber stock to dipped cord.
A cord dip phenol formaldehyde resole was prepared as follows.
______________________________________ Resin No. 17______________________________________Recipe (moles) Phenol 1.00 Formaldehyde 3.00 Sodium Hydroxide 0.075 Water 9.36Reaction temp., .degree. C 80Reaction time, hrs. 1Unreacted Formaldehyde 7.87% pH 9.0Brookfield Visc., cps 15.5Water Tolerance, % 10,000+ TSC, % 45.0______________________________________
The resin produced above was then incorporated into a series of two cord dips, the recipes of which are set forth below.
______________________________________DIP RECIPES______________________________________ Dip Recipe No.______________________________________Contents (Parts) 2 3______________________________________Vinyl pyridine latex.sup.1 100 100Resin 15.4 12.5Resorcinol 4.6 7.5TSC.sup.2 40% 40%______________________________________ .sup.1 A terpolymer of 70% 1,3-butadiene, 15% styrene and 15% 2-vinyl pyridine having a solids content of 40%. .sup.2 All dips were aged overnight before cutting down to 15% TSC (total solids content) for dipping.
Commercial aromatic polyamide tire cords were dipped in the above described cord dips with the following results.
______________________________________H-ADHESION IN NEWTON OF KEVLAR TO STOCK B______________________________________DIP RECIPE RT AFTER ONE DAY RT AFTER ONE MONTH______________________________________2 278 2853 275 252______________________________________
The above results suggest that dip aging does not adversely affect adhesion.
EXAMPLES VII THRU X
Examples VII, VIII, IX and X show the data for the effect of phenol:formaldehyde ratio of phenol formaldehyde resoles on the adhesion of glass, nylon, polyester (primer coated), and rayon, respectively, to appropriate rubber stocks. The PF resoles used represent phenol:formaldehyde mole ratio range of 1:1 to 1:3. For each cord, the adhesions gradually increase as the phenol: formaldehyde mole ratio goes from 1:1 to 1:3. The data show that the preferred range of phenol:formaldehyde mole ratio of the PF resoles is between 1:2 to 1:3. No particular advantage is expected if phenol:formaldehyde mole ratio of 1:>3 is used.
The data in Examples VII-X also show the effect of PF resole:resorcinol formaldehyde novolak ratio on the adhesion of various cords to rubber. The total amount of resin used in these dips was 20 parts/100 parts of latex solids. This level of resin was chosen based on our previous observations that for this and other similar dip systems, the optimum adhesion is generally obtained with the dips containing 15-25 parts resin/100 parts of latex solids.
For PF resoles of interest (those with phenol formaldehyde mole ratio in the range 1:2 to 1:3) the optimum adhesions for all cords lie in PF resole: curing agent range of 15:5 to 10:10. For glass, rayon, and polyester tire cords a ratio of 12.5/7.5 is generally found to be the optimum whereas for nylon dip a ratio of 15:5 gives the optimum adhesion.
This observation on nylon is identical to our earlier observations on Kevlar (another polyamide fiber) where a ratio of 15:5 generally gave the optimum adhesions. From all the data collected, so far, a ratio of 15:5 is preferred for use with the polyamide fibers and a ratio of 12.5:7.5 is preferred for use on glass, rayon, and polyesters.
The optimum adhesions obtained with the PF resoles prepared with phenol formaldehyde mole ratio of 1:3 are comparable to the corresponding adhesions obtained with the conventional dips on all cords. The adhesives presently in use provide adhesions (RT and 121.degree. C.) of 150 and 100 newtons on glass, 230 and 150 newtons on nylon, 220 and 140 newtons on rayon, and 270 and 170 newtons on polyester (D-417 primer coated) on the average.
A series of nine phenol formaldehyde resoles labelled Resins 18 thru 26 were prepared by reacting appropriate amounts of phenol and formaldehyde. Sodium hydroxide was used as the catalyst. The mole ratio of phenol formaldehyde was varied between 1:1.00 to 1:3.00. The mole ratio of phenol to catalyst used was 1:0.075 and 1:.0375. The reaction temperature used was 80.degree. C. Reaction times of 1 hour to 3 hours were used. The recipes and the physical properties of various phenol formaldehyde resoles used in this study are given in the following table.
RESIN NO.__________________________________________________________________________ 18 19 20 21 22 23 24 25 26__________________________________________________________________________Recipe (moles) Phenol 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Formaldehyde 1.50 1.25 1.00 3.00 2.00 2.50 2.50 2.00 3.00 Sodium Hydroxide 0.075 0.075 0.075 0.075 0.075 0.075 0.075 0.075 0.0375 Water 5.30 5.02 4.74 9.36 6.11 7.91 7.91 6.11 9.36Reaction Temp., .degree. C 80 80 80 80 80 80 80 80 80Reaction Time, hrs. 1.25 1.25 1.25 1 1 1 1 1 3Free Formladehyde content 0.51% 0.24% -- 7.04% 4.67% 3.30% 5.70% 2.50% 8.56% pH 9.3 9.3 9.3 9.2 9.25 9.4 9.00 9.00 8.25Brookfield Viscosity, cps. 22.5 18.0 -- 18.0 -- -- 17.5 14.5Water Tolerance.sup.1, % 700 1300 .infin. 570 970 1400 400 250Calculated TSC.sup.2, % 60 60 60 45.0 49.0 54.0 59.7 54.0 44.7__________________________________________________________________________ .sup.1 Defined as the weight percent of water added before turbidity appears .sup.2 Calculated on the basis of total phenol consumption. Some unreacte phenol is present in all resoles (thin layer chromatography and C.sup.13 NMR)?
Dips were prepared by adding varying amounts of phenol formaldehyde resoles and Penacolite R-2170 (a resorcinol formaldehyde Novolak resin made by Koppers, Inc.) to a latex. The latex used unless otherwise specified was a terpolymer of 70% 1,3-butadiene, 15% styrene and 15% 2-vinyl pyridine having a solids content of 40%. The ratio (dry basis) of total resin/latex used varied between 10/100 to 20/100, although 20/100 was the most commonly used ratio. The ratio of phenol formaldehyde resole/Penacolite was varied between 20/0 to 10/10. All dips were prepared at 40% TSC.
The procedure for making the dips was as follows. Appropriate amount of phenol formaldehyde resole was weighed and the required amount of water was added. Appropriate amount of resorcinol was then added to the above and mixed well. The resin mixture was then slowly added to the latex while stirring. The dip was stirred for about 30 minutes to get good mixing. All dips were aged at least overnight before reduction to the TSC levels for use.
______________________________________Dip Recipes______________________________________Recipe No.Contents 6 7 8 9 10______________________________________(Dry parts)Latex 100 100 100 100 100PF resole 20 17.5 15.0 12.5 10.0Resorcinol 0 2.5 5.0 7.5 10.0______________________________________
Commercial sized glass cords obtained from Owens Corning Fiberglass were dipped in the above described cord dips with the following results.
EXAMPLE VIII TABLE__________________________________________________________________________EFFECT OF PHENOL FORMALDEHYDE RATIO OF PFRESOLES ON THE H-ADHESION OF GLASS.sup.1__________________________________________________________________________ RESIN USED__________________________________________________________________________Testing Temp. 20 19 18 21 22 23P/F, Moles RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree.__________________________________________________________________________ CDip Recipe 1:1.0 1:1.25 1:1.5 1:3.0 1:2.0 1:2.5__________________________________________________________________________ 6 94 60 120 69 116 73 142 82 131 80 122 75 7 111 73 124 70 127 78 137 94 147 86 142 85 8 124 64 136 75 127 80 151 93 147 86 151 95 9 129 74 135 74 136 79 170 97 145 79 165 9710 144 81 142 76 142 78 166 101 139 79 155 88__________________________________________________________________________ .sup.1 OCF glass cord, ECG-15, 1/0 Dipping conditions: 40% TSC, 218.degree. C, 60 seconds, 0% stretch, Orifice No. 71 having a 0.066 cm diameter opening Rubber Stock Used: Stock A
Commercial nylon cords were dipped in the above described dips with the following results.
EXAMPLE VIII TABLE__________________________________________________________________________EFFECT OF PHENOL FORMALDEHYDE RATIO OF PFRESOLES ON THE H-ADHESION OF NYLON 66.sup.1__________________________________________________________________________ RESIN USED__________________________________________________________________________Testing Temp. 20 19 18 24 25 26P/F, Moles RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree.__________________________________________________________________________ CDip Recipe 1:1.0 1:1.25 1:1.5 1:2.5 1:2.0 1:3.0__________________________________________________________________________6 122 65 154 90 142 90 -- -- -- -- -- --7 137 79 188 118 207 128 -- -- -- -- 216 --8 147 90 186 100 213 134 210 130 198 132 222 --9 131 75 150 87 208 135 -- -- -- -- 216 --10 113 66 130 68 179 95 -- -- -- -- 199 --__________________________________________________________________________ e .sup.1 840/2/2 cord Dipping Conditions: 20% TSC, 238.degree. C, 80 seconds, 8% stretch Rubber Stock Used: Stock A
Commercial polyester cords were dipped in the above described dips with the following results. The polyester cords used were commercial cords obtained from DuPont. They were primed with DuPont D-417 primer. D-417 primer is a mixture of an epoxy resin and a diisocyanate (Hylene M.P.) which cures on the cord surface.
EXAMPLE IX TABLE__________________________________________________________________________EFFECT OF PHENOL FORMALDEHYDE RATIO OF PFRESOLES ON THE H-ADHESION OF POLYESTER__________________________________________________________________________ RESIN USED__________________________________________________________________________Testing Temp. 20 19 18 21 22 23P/F Moles RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree.__________________________________________________________________________ CDip Recipe 1:1.0 1:1.25 1:1.50 1:3.0 1:2.0 1:2.5__________________________________________________________________________6 101 49 109 56 114 69 194 131 178 115 187 1247 115 70 127 76 141 82 219 145 222 146 219 1468 178 112 163 103 179 104 232 160 223 144 231 1579 222 136 215 121 207 114 251 171 237 161 229 15510 239 137 243 150 236 147 250 179 234 160 224 152__________________________________________________________________________ Dipping Conditions: 20% TSC, 221.degree. C, 45 Seconds, 0% stretch Rubber Stock Used: Stock C
Commercial rayon cords were dipped in the above described dips with the following results. The rayon cords had 1650 filaments in each stand and three strands per cord.
EXAMPLE X TABLE__________________________________________________________________________EFFECT OF PHENOL FORMALDEHYDE RATIO OF PFRESOLE ON THE H-ADHESION OF RAYON__________________________________________________________________________ RESIN USED__________________________________________________________________________Testing Temp. 20 19 18 21 22 23P/F, Moles RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree.__________________________________________________________________________ CDip Recipe 1:1.0 1:1.25 1:1.50 1:3.0 1:2.0 1:2.5__________________________________________________________________________6 164 81 199 112 217 134 167 88 156 82 149 757 172 87 187 94 187 110 173 100 192 100 170 888 189 88 188 95 199 115 208 116 220 128 209 1199 185 83 184 94 196 110 240 152 228 129 246 14210 170 73 183 88 194 105 246 134 188 109 231 121__________________________________________________________________________ Dipping Conditions: 20% TSC,221.degree. C, 45 seconds, 4% stretch Rubber Stock Used: Stock A
EXAMPLE XI
The effect of total resin (PF resole + Penacolite)/latex ratio was studied to arrive at an optimum range for use in adhesives on nylon, rayon, and polyester tire cords. The results are shown in Example XI Table. The data on polyester and rayon obtained are about 10% lower than normally observed. It is assumed that all the adhesion values for rayon and for polyester are low by about the same amount and that the trend showing the effect of resin/latex ratio in the Table is representative of the actual process. It is seen from the data in the Table that about 15 parts resin/100 parts latex gives the highest adhesion for nylon, whereas for rayon and polyester the optimum resin/latex ratio appears to be between 20-25 parts resin/100 parts latex solids. It may also be important to mention that the PF resole used for nylon dips was different from that used for rayon and polyester dips in that the former contained only half as much sodium hydroxide (catalyst) as the latter.
Two phenol formaldehyde resoles labeled Resin 27 and 28 in the following table were prepared. The ingredients used on the reaction conditions are set forth in the table.
______________________________________ RESIN NO. 27 28______________________________________Recipe (moles) Phenol 1.00 1.00 Formaldehyde 3.00 3.00 Sodium Hydroxide 0.0375 0.075 Water 9.36 9.36Reaction Temp..sup.1 .degree. C. 80 RTReaction Time, hrs. 3 168 (7 days)Free Formaldehyde Content 8.56% 9.90% pH 8.25 9.10Brookfield Viscosity, cps 14.5 11.5Water Tolerance, % 250 .infin.TSC, % 44.7 44.2______________________________________ .sup.1 Temperature of the polymerizer bath
The resins produced above were then incorporated into a series of cord dips having resin/latex ratios of from 10:100 to 30:100. The ratios and the results are set forth in the table below.
__________________________________________________________________________DIP RECIPES__________________________________________________________________________EFFECT OF RESIN/LATEX RATIO ON THE H-ADHESIONOF VARIOUS CORDS TO RUBBER__________________________________________________________________________ Resin 27 Resin 28 Resin 28Fiber 840/2/2 Nylon 1650/3 Rayon 1300/3 Polyester (D-417 primer)__________________________________________________________________________Resin.sup.1 /Latex Ratio RT 121.degree. C RT 121.degree. C RT 121.degree. C__________________________________________________________________________10:100 225 -- -- -- -- --15:100 229 -- 203 107 217 14020:100 212 -- 229 120 237 15625:100 -- -- 222 126 239 15830:100 -- -- 213 135 230 153__________________________________________________________________________ .sup.1 Refers to PF resole + Penacolite. Ratio of PF resole/Penacolite used was 3/1 in all cases. Stock B was used. The dipping conditions were 20% TSC, 238.degree. C, 80 seconds and 8% stretch.
EXAMPLE XII
A reduction in the vinyl pyridine content of the latex used in the makeup of the adhesive dip reduces the cost of the dip. Dips containing blends of the vinyl pyridine latex and 50-50 styrene/butadiene latex were studied as adhesives for nylon, polyester and kevlar tire cords. A dip recipe containing 100 parts of latex, 15 parts of phenol formaldehyde resole and 5 parts of Penacolite R-2170 was used in all cases.
The ingredients and reaction condition for making the resole used are set forth in the table below:
______________________________________ RESIN NO. 29______________________________________Recipe (moles) Phenol 1.00 Formaldehyde 3.00 Sodium Hydroxide 0.075 Water 9.36Reaction Temp., .degree. C 70Reaction Time, hrs. 3 pH 9.1Calculated TSC, % 60______________________________________
The results obtained by blending the expensive vinyl pyridine latex with a relatively inexpensive butadiene styrene latex are set forth in the following table.
EXAMPLE XII TABLE______________________________________EFFECT OF LATEX COMPOSITIONON THE H-ADHESION OF VARIOUS CORDS______________________________________Ratio of Vinyl PolyesterPyridine Latex (D-417to Styrene Kevlar Nylon Primer DipButadiene RT RT RTLatex Stock B Stock A Stock C______________________________________1000:0 275 212 27275:25 268 222 28550:50 265 239 28525:75 253 226 267 0:100 239 152 201______________________________________CORD SPECIFICATIONS AND DIPPING CONDITIONS______________________________________Polyester (1300/3),D-417 primer coated: 221.degree. C, 45 sec., 0%stretchNylon 66 (840/2/2): 238.degree. C, 40 sec., 8% stretchKevlar (1500/3): 232.degree. C, 90 sec., 2% stretch______________________________________
EXAMPLE XIII
Effect of PF Resole Aging on Adhesion
In addition to being cheaper, phenol formaldehyde (PF) resoles have another advantage over the resorcinol based resoles presently being used in the tire cord adhesive dips. The useful shelf life on PF resoles is considerably higher than that of the resorcinol formaldehyde resoles. Depending upon their preparation, PF resoles may be useful for up to 100 days at room temperature (RT) whereas the resorcinol formaldehyde resoles barely last three days. The effect of aging (at RT) on the adhesive quality of PF resoles was studied for the adhesion of nylon, rayon, and polyester to rubber. The resoles used were prepared at room temperature. A standard dip recipe was used.
The adhesion data showing the effect of resole age on its adhesive quality show that the adhesive quality of PF resoles prepared at room temperature is not affected even after 100 days aging. PF resoles prepared at higher temperatures (>25.degree. C.) have somewhat shorter useful shelf life (40-60 days).
EXAMPLE XIV
The cord dips disclosed in the previous examples contained either resorcinol or resorcinol formaldehyde (RF) novolaks prepared with an acid catalyst.
The resorcinol formaldehyde novolaks or resorcinol can be replaced by resorcinol formaldehyde resins prepared in the alkaline medium. Pertinent data on the preparation of resorcinol formaldehyde resins, dip formulations and adhesion are given in Example XVI Tables I, II and III, respectively.
The adhesion data in Table III show that the RF resins prepared in the alkaline medium perform as well as resorcinol in these dips for the adhesion of various cords to rubber.
TABLE I__________________________________________________________________________EXAMPLE XIV__________________________________________________________________________PREPARATION OF RESORCINOL FORMALDEHYDE(RF) RESIN BASED CURING AGENTS__________________________________________________________________________ Curing AgentContents 1 2 3__________________________________________________________________________Deionized Water 181.6 g 210.6 g 238.5 gSodium Hydroxide (100%) 0.3 0.3 0.3Resorcinol (100%) 11.0 11.0 11.0Formaldehyde (37%) 4.1 8.1 16.2 Total 197.0 g 220.0 g 266.0 gTheoretical TSC 6.5% 6.5% 6.5%Reaction Temp., .degree. C 25 25 25Reaction Time, hrs. 6 6 6Resorcinol Formaldehyde 1/0.5 1/1 1/2(mole ratio)__________________________________________________________________________
TABLE II__________________________________________________________________________EXAMPLE XIV__________________________________________________________________________PREPARATION OF ADHESIVE DIPS__________________________________________________________________________Contents A B C D__________________________________________________________________________Vinyl Pyridine Latex.sup.1 122.0 122.0 122.0 122.0PF resin (45%).sup.2,3 16.3 16.3 16.3 16.3Resorcinol (100%) 2.5 -- -- --Curing Agent1(6.5%) -- 38.5 -- --Curing Agent2(6.5%) -- -- 38.5 --Curing Agent3(6.5%) -- -- -- 38.5Deionized Water 159.2 123.2 123.2 123.2 Total 300 300 300 300TSC 20% 20% 20% 20%__________________________________________________________________________ .sup.1 41% total solids .sup.2 Phenol formaldehyde resin prepared at 70.degree. C. .sup.3 Mole ratios of phenol:formaldehyde:sodium hydroxide were 1/3/.075.
TABLE III______________________________________EXAMPLE XIV______________________________________H-ADHESION DATA______________________________________ Polyester (DesmodurCord Rayon TT primer) Kevlar Nylon______________________________________ Stock D Stock C Stock B Stock ADip RT 121.degree. C RT 121.degree. C RT 121.degree. C RT 121.degree. C______________________________________A 202 122 239 159 238 145 202 144B 208 134 229 154 248 155 235 168C 204 126 225 150 247 153 217 172D 195 122 216 152 244 148 258 187______________________________________Cord Processing Conditions:Rayon 221.degree. C, 60 sec., 4% stretchPolyester (Desmodur TT primer) 221.degree. C, 45 sec., 0% stretchKevlar 232.degree. C, 90 sec., 2% stretchNylon 238.degree. C, 80 sec., 8% stretch______________________________________
While the adhesive containing reinforcing elements of this invention can be adhered to a vulcanizable blend of natural rubber, polybutadiene rubber, and rubbery butadiene-styrene copolymer by curing the same in combination together, it is apparent that said adhesive containing reinforcing element can be adhered to other vulcanizable rubbery materials by curing or vulcanizing the same in combination with the rubber, such as one or more of the foregoing rubbers as well as nitrile rubbers, chloroprene rubbers, polyisoprenes, vinyl pyridine rubbers, acrylic rubbers, isoprene-acrylonitrile rubbers and the like and mixtures of the same. These rubbers prior to curing can be mixed with the usual compounding ingredients including sulfur, stearic acid, zinc oxide, magnesium oxide, accelerators, antioxidants, antiozonants and other curatives and the like well known to those skilled in the art for the particular rubbers being employed.
Fibers, yarns, filaments, cords or fabric and the like coated with the adhesive of the present invention can have from about 3 to 7% by weight (dry) total solids from the adhesive dip on the cord based on the weight of the cord and can be used in the manufacture of radial, bias, or belted-bias passenger tires, truck tires, motorcycle and bicycle tires, off-the-road tires, airplane tires, transmission belts, V-belts, conveyor belts, hose, gaskets, rubbers, tarpaulins, and the like.
The reinforcing elements which can be used are known in the art and described in detail in a large number of U.S. Patents.

Number	Name	Date	Kind
3888805	Van Gils et al.	Jun 1975
3930095	Van Gils et al.	Dec 1975

Pollution free method of making phenol formaldehyde resole tire cord dip and product

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