PET／60PABA 热致型液晶共聚酯的合成与表征

摘要

将对羟基苯甲酸（PHB）的乙酰化产物对乙酰氧基苯甲酸（PABA）引入聚酯（PET）分子主链结构中，成功制备出共聚酯 PET /60PABA，研究了聚合温度和催化剂浓度对共聚酯合成的影响。通过差示扫描量热（DSC）、X 射线衍射（XRD）、超导核磁共振（NMR）、凝胶渗透色谱（GPC）、偏光显微镜（POM）和毛细管流变仪等手段对共聚酯的分子结构与液晶形态进行表征，结果表明，共聚酯 PET /60PABA 几乎为完全无规共聚，熔融状态下具有向列型热致液晶聚合物的典型特征。%The thermotropic liquid crystalline copolyesters PET /60PABA were successfully perpared by intro-ducing P-hydroxybenzoic acid(PHB)units into the polyethylene terephthalate(PET)chain.The effects of ploymer-ization temperature and catalyst concentration on the copolyester synthesis were stuidied.The macromolecular struc-ture and the thermotropic liquid crystalline behavior of copolyesters were analyzed by DSC、XRD、NMR、GPC、POM and capillary rheometer.The results showed that PET /60PABA was a completely random copolymer,and it has a typical behavior of nematic thermotropic liquid crystalline in melt state.