| 摘要 |
1,267,606. Crystalline polyesters. GENERAL TIRE & RUBBER CO. 14 Aug., 1969 [1 May, 1969], No. 40776/69. Addition to 1,225,803. Headings C3P and C3R. A crystalline polyester comprises the reaction product or at least partially isomerized reaction product of a cyclic ether or thioether of the formula I where R 1 and R 2 are the same and are hydrogen or C 1-4 alkyl and Y is oxygen or sulphur, and at least one anhydride of a dicarboxylic acid, the reaction being carried out in the presence of a double metal cyanide complex catalyst, said polyester having a molecular weight of about 1000 to 10,000. Preferred reactants are isobutylene oxide and maleic and/or phthalic anhydride. Polyesters containing maleate groups may be at least partially isomerized to form fumarate groups. - . A fibreglass composite material comprises (a) a polyester of the invention, (b) a cross-linking or curing monomeric material, (c) 15 to 75 parts by weight of glass fibres per 100 parts by weight of (a) + (b), (d) 20 to 300 parts by weight of a finely divided filler per 100 parts by weight of (a) + (b) and (e) a free radical catalyst, the ratio of (a) to (b) being from 75: 25 to 50: 50 parts by weight. Preferably, the component (b) is a copolymerizable ethylenically unsaturated material such as diallyl phthalate, styrene, divinyl benzene, vinyl toluene, vinyl acetate, methyl methacrylate, ethylene glycol diacrylate, vinyl benzoate and mixtures thereof. The filler may be clay or silica and the catalyst is preferably a peroxide or an azo compound. |
