摘要 |
1352063 Fibrous laminates IMPERIAL CHEMICAL INDUSTRIES Ltd 23 Dec 1971 [8 Jan 1971] 1061/71 Heading B5N [Also in Division C3] Laminates may be prepared by heating under pressure stacks of fibrous mats which have been impregnated with polymerizable compositions comprising (a) 5 to 95 weight per cent of at least one prepolymer of structure in which R 1 is an organic group which may contain at least one cyclic group in the macromolecular chain of the prepolymer, R 2 has the structure -[CHR 4 CHR 5 O] a -Ar-[OCHR 4 CHR 5 ] b - wherein Ar is a divalent aromatic group in which each free valency is on an aromatic carbon atom, R 4 and R 5 are hydrogen or alkyl, and a and b are integers, and R 1 and R 2 are such that there are not more than 30 atoms in the chain between adjacent cyclic groups, n is 1 to 20 and when n is 1 and only R 2 contains at least one cyclic group in the chain there are not more than 30 atoms in the chain between the cyclic group in R 2 and the nitrogen atom attached to X, R 3 is hydrogen or hydrocarbyl and X is a divalent group, and (b) 95 to 5 weight per cent of at least one terminally unsaturated monomer free from isocyanate reactive groups. Many suitable reactants are listed and in examples (7) a plurality of chopped strand glass fibre mats are placed in a mould and impregnated with styrene solutions of "vinyl"-ended prepolymers derived from 2,2- bis-(p-hydroxyphenyl)propane/propylene oxide condensate-4,4<SP>1</SP>-diisocyanato diphenylmethane polyurethane and 2-hydroxyethyl methacrylate, and polymerization is effected with heat and pressure in the presence of methyl ethyl ketone peroxide and a cobalt complex; and (9) 26 pieces of carbon fibre mat impregnated with a mixture of styrene, the above "vinyl"-terminated prepolymer and di-t-butyl peroxide are stacked in a mould and polymerization effected by heating.
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