“…Since water is a nonozone depleting, non-toxic and cheap blowing agent, some researches on water blown rigid foams and their applications have been performed [4][5][6] . However, compared to the CFCs blown rigid foams, water blown rigid foams encounter some problems such as dimensional stability, foam flow-ability, formulation viscosity, friability, substrate adhesion, insulation performance, K-factor aging and blowing agent solubility [7,8] . A broad study of different effects of polyol, blowing agent, MDI and catalyst on foam properties is very necessary to address these issues.…”