| abstract |
1,150,429. Unsaturated polyurethane resinrubber compositions. SINCLAIR RESEARCH Inc. 17 June, 1966 [18 June, 1965; 22 March, 1966], No. 27108/66. Headings C3P and C3Q. A composition comprises a hydrocarbon rubber and a polyurethane resin made by reaction of a diisocyanate with a polymer which is an addition polymer of 0 to 75% by weight of an alpha-mono-olefinic monomer of 2 to 12 carbon atoms and 100 to 25% by weight of a C 4 to C 12 conjugated diene, which polymer has an average of at least 1À8 predominantly primary, terminal, allylic hydroxyl groups per molecule, has a viscosity at 30‹ C. of 5 to 20,000 poises, has a number average molecular weight of 400 to 25,000, and has the majority of its unsaturation in the main hydrocarbon chain, said polyurethane being uncured or only partially cured when blended with said rubber. If desired, the polyurethane can be modified by the presence of diamines, glycols, &c. Suitable diene prepolymers are homopolymers of butadiene and copolymers of butadiene and styrene or acrylonitrile. Exemplified rubbers are natural rubber, ethylene propylene terpolymer, styrene-butadiene rubber and nitrile rubber. |