New rigid-rod poly(benzoxazole-imide)s containing chloro-substituted p-phenylene units in the main chain

✍ Scribed by Guey-Sheng Liou

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 160 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19991115)37:22<4151::aid-pola14>3.0.co;2-d

✦ Synopsis

A series of new poly(o-hydroxy amide-imide)s with high molecular weights were synthesized by low-temperature solution polycondensation from a preformed imide ring and chloro-or dichloro-substituted p-phenylene-containing diacid chlorides of 2,5-bis(trimellitimido)chlorobenzene or 1,4-bis(trimellitimido)-2,5-dichlorobenzene and three bis(o-amino phenol)s. All the poly(o-hydroxy amide-imide)s were readily soluble in a variety of organic solvents such as N-methyl-2-pyrrolidone and N,Ndimethylacetamide. Transparent and flexible films of these polymers were cast from their solutions. The cast films had tensile strengths ranging from 88 to 102 MPa and elongations at break of 8 -12%. Subsequent thermal cyclodehydration of the poly(ohydroxy amide-imide)s afforded novel poly(benzoxazole-imide)s. The poly(benzoxazoleimide)s exhibited glass-transition temperatures in the range of 310 -338 °C and were stable up to 500 °C in nitrogen, with 10% weight-loss temperatures recorded between 550 and 570 °C in nitrogen.