中文摘要：

研究了聚对亚苯基苯并二噁唑（PBO）在强质子酸多聚磷酸（PPA）和甲基磺酸（MSA）溶液中的稳定性,包括溶液温度、超声波对PBO溶液稳定性的影响以及环境气氛对PBO溶液光稳定性的影响。结果表明：在避光条件下长期放置时,PBO-MSA溶液对于温度比较敏感,而PBO-PPA溶液即使在高温下也很稳定;PBO在MSA溶液中的化学降解可分为两部分：首先是PBO本身的酰胺弱键断链,其次是噁唑环开环形成酰胺键并断链;PBO-MSA溶液在超声波作用下的降解属于应力诱导降解,符合超声波降解断链的一般规律;PBO溶液在氮气气氛中对紫外光相对稳定,而在氧气中光降解速率很快。

英文摘要：

The effect of temperature,ultrasonic and environment atmosphere on the stability of poly（p-phenyl benzobisoxazole）（PBO） in strong protonic acid solutions,such as poly（phosphoric acid）（PPA） and methanesulfonic acid（MSA）,was studied.Results show that in dark environment,PBO-MSA solution is sensitive to the temperature,whereas PBO-PPA solution is stable even at high temperature.The degradation process of PBO on the MSA solution is consisted of two steps： first,the o-hydroxy amide structure in the PBO molecule degrades;then,the benzoxazole ring openes and formes o-hydroxy amide linkage structure,o-hydroxy amide linkage degrades subsequently.The degradation of PBO-MSA solution under ultrasonic belongs to stress-induced,which is consistent with the classic ultrasonic degradation mechanism.The results also show that PBO solution is stable under nitrogen,whereas the speed of photo-degradation is fast when environment atmosphere is oxygen.