| 摘要 |
1353052 Glass fibre/resin laminates GENERAL ELECTRIC CO 19 April 1971 [27 March 1970] 20521/71 Heading B5N [Also in Division C3] A process for preparing a polyimide comprises reacting 0À5 to 2 moles of an arylene diamine per mol of an anhydride wherein R is an aliphatically unsaturated hydrocarbon or halogen-substituted hydrocarbon radical, in the presence of acetic acid. Reaction may be effected in a solvent at 25 to 250‹ C. Various reactants and solvents are exemplified. The products may be used for coating, adhesive or moulding applications and may be cured at 180 to 300‹C. optionally in the presence of anionic or free radical catalysts, e.g. dicumyl or benzoyl peroxide, cumene hydroperoxide or t-butyl perbenzoate, or fillers, e.g. silica, graphite, glass or carbon fibres, asbestos or TiO 2 . Laminates.-In Example 2, glass cloth is immersed in a 25% solution in dimethyl formamide of a polyimide obtained by reacting 59 parts maleic anhydride and 79 parts 4,41- diaminodiphenyl methane in the presence of 500 parts acetic acid. After air drying a stack of impregnated cloth is laminated at 250‹C. and 1000 p.s.i. |
