【摘要】 以均苯四甲酸二酐、4,4′二胺基二苯醚为原料,通过缩聚反应制备了聚酰胺酸,采用凝胶渗透色谱(GPC)考察了反应时间对产物重均摩尔质量的影响;测定了干燥过程中聚酰胺酸凝胶膜溶剂含量的变化;并利用电子万能试验机研究了聚酰胺酸薄膜的拉伸工艺。结果表明:聚酰胺酸的适宜反应时间为6h,此时其重均摩尔质量趋于稳定。随着干燥温度的升高和时间的延长,凝胶膜的溶剂含量逐渐减少。分析得到较好的拉伸条件是干燥温度为130℃,溶剂质量分数为30%左右的凝胶膜。聚酰亚胺薄膜经拉伸后,其拉伸强度和模量均随拉伸比的增大而增加。更多还原

【Abstract】 Polyamide acid was prepared by means of polycondensation,taking PMDA and ODA as raw materials,and the effect of reaction time on the change of the weight-average molar mass of polyamide acid was measured by gel permeation chromatography(GPC).The change of solvent content of polyamide acid film during drying was determined by constant temperature oven,and the stretching technology for the film was investigated by electronic universal testing machine.The results showed that the feasible reaction time for polyamide acid was 6 h,at this time the weight average molar mass went to stable.The solvent content of polyamide acid film decreased with the rising of the drying temperature and the prolongation of the drying time.A suitable stretching condition was that the drying temperature was 130 ℃ and the solvent mass fraction was about 30%.After the stretching the tensile strength and modulus of the film increased with the increase of the draw ratio.更多还原