“…Polyurethane is one of the most versatile materials which have been widely used in furniture, roofs, medical equipment, automotive interior materials, etc . Rigid polyurethane foams (RPUF), for one, is extensively applied as external wall insulation, foundation reinforcement of building, and decoration due to its excellent properties such as excellent mechanical properties, low thermal conductivity, rapid expansion and solidification, excellent corrosion, and water resistance …”