Epoxy plus liquid crystalline epoxy coreacted networks: II. Mechanical properties

The effect of coreacting diglycidyl ether of bisphenol F (DGEBP-F) with dig lycidyl ether of 4,4'-dihydroxybiphenol (DGE-DHBP) on mechanical properties is investigated. DGE-DHBP shows a liquid crystal (LQ transition upon curin g. Tensile, impact and fracture toughness test results are evaluated. Dynam ic mechanical analysis is conducted to determine the effect of the DGE-DHBP component. Scanning electron microscopy of fracture surfaces shows changes in failure mechanisms compared to the pure components. The results indicat e that the mechanical properties of these blended samples are significantly improved at 10-20% by weight of DGE-DHBP. This is a consequence of the rig idity of the LC component which thus provides the reinforcement. (C) 2001 E lsevier Science Ltd. All rights reserved.