摘要 |
A catalyst for forming ambient temperature stable diamino-diphenyl sulfone-epoxy composition comprises the half-salt of a strong aromatic sulfonic acid such as toluene sulfonic acid and an imidazole, preferably an alkylated imidazole such as 2-ethyl-4-methylimidazole. The composition fully cures at moderate temperature to form a humidity resistant resin having a high heat distortion temperature and can be impregnated onto reinforcing fibers such as graphite to form composites.
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