Modification of DGEBA with diimide‐diacids derived from bicyclo[2.2.2]oct‐7‐ene‐2,3,5,6‐tetracarboxylic dianhydride and crosslinking study

Abstract

Epoxy resins derived from diimide–diacids obtained from bicyclo[2.2.2.]oct-7-en-2,3,5,6-tetracarboxylic dianhydride and diglycidyl ether of bisphenol A were synthesized and characterized by spectroscopic techniques and thermal analyses. A further crosslinking using hydroxylic groups using dianhydride or diisocyanate as a hardener was also carried out. These processes led to crosslinked materials, but a DSC study does not show a straightforward relationship between the amount of hardener used and reaction enthalpiies, which suggests a complicated reaction mechanism. On the other hand only a slight increase in Tg values was observed during the curing process. No substantial differences between the thermal characteristics of linear and crosslinked polymers wer observed. © 1996 John Wiley & Sons, Inc.