反应详情

温度

250 °C

A polymerization flask equipped with nitrogen inlet and outlet tubes and mechanical stirrer was thoroughly flamed and purged with nitrogen. To this was added a mixture containing 5.0 g (14.5 mmole) of 2-[p-carbophenoxyphenyl]-5,6-diaminobenzimidazole and 25 g of diphenyl sulfone. The reaction flask was then slowly heated to 250° C and maintained at that temperature for 6 hours. During this time, phenol sublimed from the reaction mixture, and a precipitate formed. The flask was cooled to 125° C and the polymer suspension poured into 500 ml of methanol. The polymer thus precipitated was collected on a filter frit, washed several times with small portions of methanol, and dried. Reprecipitation from methane sulfonic acid into methanol, followed by successive washings with 5% ammonium hydroxide, methanol and benzene, yielded 2.9 g of benzimidazole polymer as a dark tan powder, exhibiting an inherent viscosity of 1.1 dl/g in methane sulfonic acid (0.35 g/dl).

1. customA polymerization flask equipped with nitrogen inlet and outlet tubes and mechanical stirrer
2. temperaturewas thoroughly flamed
3. custompurged with nitrogen
4. additionTo this was added a mixture
5. temperaturemaintained at that temperature for 6 hours
6. customa precipitate formed
7. temperatureThe flask was cooled to 125° C
8. customThe polymer thus precipitated
9. customwas collected on a filter frit
10. washwashed several times with small portions of methanol
11. customdried
12. customReprecipitation from methane sulfonic acid into methanol
13. washfollowed by successive washings with 5% ammonium hydroxide, methanol and benzene