Abstract: Polyurethaneimide (PUI) foam was prepared from polyphenyl polymethylene polyisocyanates, pyromellitic dianhydride, and castor oil with prepolymer method using HCFC-141b. The effect of amount of HCFC-141b on the chemical structure, cell structure, open cell content, density, volume expansion rate，mechanical properties, and thermal behavior was analyzed. It showed that, HCFC-141b did not change the chemical structure and thermal behavior of the foam. With the increase of HCFC-141b from 0 % to 10 %, average cellular diameter, open cell content, and volume expansion rate increased, while the density and compressive strength decreased. Thus the structure and properties of the PUI foam could be adjusted through changing the amount of HCFC-141b.

Key words: polyurethane-imide, foam, 1, 1-dichloro-1-a fluorine ethane, structure, property