POLYHYDRIC PHENOLS AS CHAIN EXTENDERS FOR CERTAIN BISMALEIMIDE RESINS

摘要

A class of di-ortho-substituted bismaleimides undergo uncatalyzed Michael addition with polyhydric phenols to afford chain-extended bismaleimides having a significantly wider processing window than the non-ex tended parent. The fully cured resins show improved fracture toughness, generally have comparable or superior dielectric constant an dielectric loss, and show no degradation in other properties such as resistance to moisture, to methylene chloride, and coefficient of thermal expansion.