Abstract: A series of polyoxypropylene-g-epoxy resins(epoxy-g-PO) were synthesized from epoxy resin(epoxy) and polyoxypropylene with molecular weights from 230 to 1550. The grafting efficiency for these epoxy-g-POs was around 0.96. The morphology of such epoxy-g-POs and their networks were examined by means of FTIR, DSC and TEM, respectively. Partial microphase separation was observed in graft networks containing longer side chains(M_w≥950), while the graft network having short grafts(M_w=230) exhibited a compatible system. The impact strengths of epoxy cured with less amount of epoxy-g-PO(5% to 10%,wt) were enhanced appreciably, while the tensile strength and the heat resistance for these graft networks remained nearly as those of epoxy network. All the physical properties of the graft epoxy networks could be well related to their morphologies.

Key words: epoxy resin, polyoxypropylene, synthesis, grafted polymer network, toughness, morphology