GB1415753A - Methods of making fibre reinforced rubber - Google Patents

Abstract

1415753 Bonding fibres to rubber MONSANTO CO 25 Jan 1973 [26 Jan 1972] 3953/73 Addition to 1367362 Heading B5N [Also in Divisions D1 and C3] Fibre reinforced rubber having the fibre bonded to rubber is made by incorporating fibre, a formaldehyde donor and an adhesionenhancing amount of an essentially saturated polymer of resorcinol into a vulcanizable rubber stock and heating to form a vulcanized fibre bonded rubber product, the resorcinol polymer being obtained by condensing resorcinol with a C 3 -C 10 olefinic alcohol or a precursor thereof, e.g. allyl alcohol, allyl acetate or allyl ether, the condensation at least during the final stages being carried out under acidic conditions. The weight ratio of polymer to rubber is generally from 0À5 to 10 : 100. Suitable formaldehyde donors are hexamethylenetetramine, hexamethoxymethylmelamine, cyclotrimethyltriamines, and [(hydroxymethyl)ethylidene]- alkylamines. Suitable fibres include polyester, rayon, nylon, Al, Cu, Sn, steel, brass-plated steel, Al-steel alloy, glass, cotton, wool or wood-cellulose fibres. The fibre may be untreated or treated with RFL or the essentially saturated resorcinol polymer before adding to the rubber stock. In the example a resorcinol polymer containing free resorcinol is prepared by condensing allyl alcohol and resorcinol using HCl or H 2 SO 4 as catalyst. The polymer is added to a rubber stock comprising smoked sheet rubber, styrene-butadiene copolymer rubber, furnace carbon black, silica, zinc oxide, stearic acid, hexamethylenetetramine, sulphur and N-tertbutyl - 2 - benzothiazolesulphenamide. Untreated nylon and rayon tyre cords are embedded in the rubber stock which is then cured. Rubbers which may be used include natural rubber and synthetic rubbers, e.g. styrenebutadiene copolymer, isobutylene isoprene copolymer, ethylene-propylene-diene terpolymers, butadiene-acrylonitrile copolymers, polychloroprene and polyisoprene.