Abstract: The use of 3-[3-(dimethylamino)propyl]-propionamide (Formula I) and 3,3'-{[3-(dimethylamino)propyl]imino}bis-propanamide (Formula II) as catalysts in the production of polyurethanes.

Abstract: The present invention relates to a microporous membrane and a process for producing thereof, especially a microporous membrane which can be used for microfiltration, has excellent resistance to chemicals, and a process for producing thereof.The present invention provides a microporous membrane having excellent resistance to chemicals, and a microporous membrane which facilitates waste disposal, and a process for producing thereof.The microporous membrane has a bubble point value measured by the use of ethanol (by the test method of JIS K3832) falling in the range of from 10 kPa to 1000 kPa and comprises a polymer prepared by ring opening polymerization of a compound represented by chemical formula (I) or a polymer which is a ring opening polymer or ring opening copolymer represented by chemical formula (II). An example of the ring opening ring polymer or ring opening copolymer is a norbornene resin.

Abstract: A heat insulator made of shape memory polymer foam which has good moldability and changes greatly in elastic modulus above and below its glass transition point, and a heat insulator as mentioned above in which the polymer foam is polyurethane produced by prepolymer process from a composition containing a blowing agent, said composition being composed of a difunctional diisocyanate, a difunctional polyol, and a difunctional chain extender containing active hydrogen in a molar ratio of 2.00-1.10:1.00:1.00-0.10, said polyurethane containing approximately equal amounts of NCO groups and OH groups at the terminals of the molecular chains and having a glass transition point of -50.degree. to 60.degree. C. and crystallinity of 3 to 50 wt %.