Aromatic polybenzoxazoles bearing ether and isopropylidene or hexafluoroisopropylidene units in the main chain

✍ Scribed by Sheng-Huei Hsiao; Chou-Huan Yu

• Book ID: 102662099
• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 520 KB
• Volume: 199
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/(sici)1521-3935(19980701)199:7<1247::aid-macp1247>3.0.co;2-y

✦ Synopsis

A series of poly(o-hydroxyamide)s having high molecular weights were synthesized by means of low-temperature solution polycondensation of 4,4'-[isopropylidenebis(1,4-phenylene)dioxy]dibenzoyl chloride (1) and 4,4'-[hexafluoroisopropylidenebis( 1,4-phenylene)dioxy]dibenzoyl chloride (2) with three bis(o-aminopheno1)s. Subsequent thermal cyclodehydration of the poly(o-hydroxyamide)s afforded polybenzoxazoles. All poly(o-hydroxyamide)s are readily soluble in a variety of solvents, whereas the polybenzoxazoles are insoluble with one exception. The polybenzoxazoles exhibit glass transition temperatures in the range of 218-231 "C and are stable up to 500°C in air or nitrogen, with the 10% weight loss temperatures being recorded between 553-607 "C in nitrogen.