Abstract
SynopsisInfluence of crosslinking density, bulkiness and rigidity of the main chain on the properties of the epoxy cured products was investigated. Incorporation of rigid structure i.e. 4,4’-biphenylene and 2,6-naphtylene moiety, in the backbone was effective for increasing fracture toughness and lowering thermal expansion, which was thought to depend on the large free volume fraction caused by the steric hindrance around crosslinking points. According to the above concept, polyfunctional epoxy resins containing rigid backbone were synthesized for industrial applications in consideration of increasing thermal property and moldability.
