聚酰胺酸合成工艺研究

Investigation on the technology of synthetic polypyromellitamic acid

采用超声波在线测量溶液粘度的方法 ,研究了合成聚酰胺酸过程中实验条件的影响 ,并对实验结果进行分析 ,由此确定了合成高分子量聚酰胺酸的最佳实验条件。研究表明 :在加料次序为先加二胺后加二酐 (二酐与二胺的摩尔比为 1 .0 1～ 1 .0 2 :1 )、试剂中含水量尽可能少 ,反应温度 0～ 5℃、反应时间以溶液粘度到达最大值为止的条件下 ,所合成的聚酰胺酸溶液粘度最大 ,可满足惯性约束聚变( ICF)

In developing gas filled hohlraum targets, fabrication of polyimide with thickness no more than 1μm plays an important role, and its kernel technology is synthetic polypyromellitamic acid. The solution viscosity is measured during the synthetic process by the method of supersonic wave. Preliminary experiments have been performed to determine the effects of reaction conditions in order to get high molecular weight in the solution. The best synthetic condition is concluded as follows: solid pyromellitic dianhydride should be added to diamine solutions, mole ratio of dianhydride and diamine should be 1.01～1.02∶1, the reaction temperature should be 0～5℃, water in solvent should be least and reaction should be stopped in suitable time.