| abstract |
Thermally-reversible polymer compositions are obtained by reacting compounds with isocyanate and labile-hydrogen functionality. High-performance characteristics are incorporated into the polymer by using polyimide, aromatic polycarbonate, aromatic polyester, polyphenylene sulfide, and poly(parabanic acid) oligomers. Low-temperature flexibility and toughness are imparted to the polymers by using prepolymers such as polycaprolactone diols, polytetramethylene ether glycols and polyaliphatic carbonate diols. Ionic bonding and liquid-crystal functionality may also be incorporated into the compositions. The compositions are useful as hot-melt adhesives, coatings, and moldings and in injection reaction molding applications and composite and laminate fabrication. |