摘要 |
Thermoplastic polycarbonate-ABS resin is rendered flame retardant by blending with the resin an O,O-diaryl-N-arylphosphoramidate, an arylene-N,N'-bis(O,O-diarylphosphoramidate) in which the nitrogen atoms are in the 1,3 or 1,4 positions on an arylene ring, or an N,N'-piperazinediylbis(O,O-diarylphosphoramidate). These flame retardants are halogen-free. They provide molded objects having high heat distortion temperatures, and high softening temperatures. Flame retardants of these types have been found to be thermally stable at temperatures of at least 260 DEG C, and they did not discolor the polymer composition during exposure to molding temperatures. |