溶致液晶聚对苯二甲酰对苯二胺的合成及性能

Synthesis and Performance of Lyotropic Liquid Crystalline Polymer Poly(l,4 - phenylene terephthalamide)(PPTA)

系统研究了影响聚对苯二甲酰对苯二胺(PPTA)对数比浓粘度的诸多因素,从而确定了最佳聚合工艺条件,并根据此工艺条件合成出了对数比浓粘度4.0以的PPTA聚合体,用偏光微镜、红外光谱、旋转粘度计和热失重分析对其结构及液晶性进行了研究和分析,结果表明,本实验所制得的聚合体确系PPTA结构,且属向列相液晶。用该聚合体初纺成的芳纶纤维(YS-AF1414)纤度为1.4旦,拉伸强度19.7克/旦,拉伸模量为450克/旦,性能指标接近美国Kevlar29的水平。

Many factors which influenced the inherent viscosity of PPTA were investigated. Systematically through large amounts of experiment the best tehnological conditions of polymerization were determined. PPTA polymers whose inherent viscosity was above 4.0 were prepared in these technological conditions. Its structure and liquid crystallinity were studied through polarizing microscope, infrared spectrum, whirl viscosimeter and thermogravimetry. It was obvious that the polymers prepared in the experiment were surely ' ploy ( 1 , 4-phenylene terephthalamide), and it belonged to nematic liquid crystal phase. The denier of aro matic fiber-II (YS - AF1414) initially span from the PPTA polymers was 1.4, tensile strength was 19.7g/d, tensile modulus was 450g/d. The performance indexes were similar to those of Kevlar 29 (U.S.A.).