WATER-BLOWN POLYURETHANE RIGID FOAMS MODIFIED BY CHEMICAL PLASTICATION

Water-blown polyurethane rigid foams are getting more and more attention,because the traditional blowing agent HCFC141b has already been abolished to prevent the ozone layer from destruction.However,the polyurethane rigid foams blown by water have serious defects,i.e.friability and resulting lower adhesion strength.Thus,the purpose of this study is to resolve the problems by chemical plastication.The maleate was added to polyol-premix containing water or to polyisocyanate,with both of which maleate does not react.To prove the reaction when polyol-premix and polyisocyanate were mixed,the model composite was synthesized and analyzed by IR,NMR and ESI(MS).Furthermore,a series of water-blown polyurethane rigid foams added different amount maleate were successfully prepared.By testing impact strength and adhesion strength of the foams,the actual effect of adding maleate was obtained.