Abstract
Polymer networks (MC-V) containing small amounts of thermotropic liquid crystalline poly (p-oxybenzoate-co-ethylene terephtalate) (LCP) have been prepared by causing a bisphenol-A-type epoxy resin to cure in a LCP/epoxy micro-dispersed state. Also, additional polymer networks, namely the heat treated specimens (MC-H), have been prepared by heating MC-V under the melting temperature of LCP.
Physical proterties of MC-V were studied by comparing with those of neat epoxy resin. Modulus at glassy state (E'g), glass transition temperature (Tg) and elongation at break (ΔL) of MC-V were larger than those of neat epoxy resin. These features of MC-V resembled those of what is called “molecular composite”. E'g and ΔL of MC-H increased futher compared with those of MC-V. That is, the reinforcing efficiency of LCP could be increased further by heat treatment of MC-V. From the changes in mechanical dispersion, birefringence and infrared spectra, it can be deduced that the dispersed state of LCP is improved and the interaction between LCP and epoxy resin matrix is strengthened accompanying the heat treatment of MC-V.
