反应详情

In the following examples Epon 828 is the reaction product of epichlorohydrin and bisphenol A having an epoxide equivalent value of 175-210 and a viscosity at 25° C. of 10,000-20,000 cps. and sold by Shell Chemical Company. D.E.N. 438 is a Dow Chemical Company epoxy resin synthesized by the reaction of epichlorohydrin and the product obtained by the reaction of phenol and formaldehyde in an acid solution having an epoxide equivalent value of 176-181 and a viscosity of 35,000-70,000 cps. at 52° C. NMA, Nadic methyl anhydride, is a mixture of methyl bicyclo (2.2.1)heptane-2,3-dicarboxylic anhydride isomers sold by Allied Chemical Corporation. BTDA, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, is sold by Gulf Oil Chemicals Company. In the examples 7-inch by 7-inch strips of 181 fiber glass cloth having Linde A1100 silane finish were used. The resulting 7-inch by 7-inch laminates were cut to the proper dimension as required for the indicated ASTM test. The flexural strengths were determined at either 73° F. or 500° F., as indicated in the following examples.

1. customat 25° C.