1、Good toughness，The average molecular weight is higher，which can improve the toughness of hard foam products，and improve thermal stress resistibility and anti cracking resistibility of foam products. 2、Good cohesiveness，be with less low molecular compounds content，no brittling，has good adhesive power with steel plate,plastic,walls and other base material ，to reduce the occurrence of uncoating abnormal situation between foam and base material. 3、Delicate foam，to react with isocyanate, the end products which are with delicate foam and have a lower thermal conductivity，which can improve the heat preservation ability. 4、Good compatibility, the composition of the materials, which is made from HM-635A, foaming agent and auxiliary agent, will not appear cloudy, stratification, metamorphism and other phenomena.