Epoxy resins and polyurethanes — mutual modifying influence.
Part II. Interpenetrating polymer networks (IPN)
Polimery 2003, No 9, 591
Summary — The methods of epoxy resins (BP) and polyurethanes (PUR) mutual modification leading to the formation of interpenetrating polymer networks (IPN) and graft polymer networks (graft-IPN) were presented on the basis of literature data. Main aim of BP modification is its elasticity irnproving. EP modification with PUR containing functional groups (namely OH, NH2, NCO or anhydride groups) or urethane — acrylic systems was discussed. Rigid PUR foams modification with BP was also presented. Additionally EP modification with low molecular weight isocyanates, acting as substitutes of PUR with reactive groups, has been described. The effects of EP:PUR weight ratio, molecular weight of isocyanate component and a degree of grafting between both polymer net-works on the morphology and mechanical and thermal properties of the products were characterized. EP and PUR phase separation determining the proper elasticity of the products was also presented.
Keywords: epoxy resins, functionalized polyurethanes, mutual modification, interpenetrating polymer networks, useful properties