BISMALEIMIDE MODIFIED BY EPOXY-RESIN AND PHENOL OR HYDROQUINONE

A homogeneous liquid with good storage-stability was obtained by heating the mixture of N,N'-4,4'-diphenylmethane-bismaleimide (BMI), bisphenol A type epoxy resin (Ep828), and phenol (PhOH) or hydroquinone (HQ). For studying the mechanism of this reaction, N-phenylmaleimide (PMI) and phenyl glycidyl ether (PGE) were used as model compounds for BMI and Ep828, respectively. Main reaction was the the radical polymerization initiated by the charge-transfer complex formed between PMI and PhOH. The product {-(4BMI)n-} of this reaction had good compatibility with unreacted Ep828 and thus the mixture existed as a homogeneous liquid. The reaction products of BMI/Ep828/PhOH or HQ were cured with 2-ethyl-4-methyl imidazole (2E4MZ) and 4,4'-diaminodiphenylmethane (DDM). The heat-resistance of the cured resins modified with HQ was higher than that of the cured systems modified with PhOH.