EFFECT OF SILICONE ON DYNAMIC-MECHANICAL PROPERTIES OF EPOXY-RESIN FILLED WITH IMIDE POWDER

The dynamic mechanical properties of epoxy resin and epoxy-silicone al loy filled with thermoplastic polyimide powder have been studied over a temperature range of -150 to 250 degrees C at the frequencies of 35 and 110 Hz and related to the morphological structure of composites ob served by scanning electron microscopy. The incorporation of polyimide raised the glass transition temperature (T-g) of both epoxy resin and epoxy-silicone alloy. The storage modulus (E') of composites increase d with increasing volume fraction of imide powder. E' of epoxy-silicon e alloy composites was higher than that of epoxy resin though the sili cone had a low storage modulus. This fact was explained by assuming th at below T-g, the presence of silicone in the matrix facilitated molec ular rearrangement during cooling from the cure temperature and above T-g, increased the interaction between filler particles and the matrix .