热致液晶共聚酯与聚酯热塑弹性体复合物的制备与性能

原位缩聚法制备了一系列(对羟基苯甲酸-对苯二甲酸-间苯二酚)(HB-TA-RES)热致液晶共聚酯与聚对苯二甲酸丁二酯-聚四亚甲基醚热塑弹性体(PBT-PTMG)复合物,并用POM,TGA,WAXD,SEM及动态应力流变仪等手段进行了表征.复合物在较宽的共聚酯含量范围(30 wt%~70 wt%)或共聚酯组成不同时(共聚酯中HB含量20 mol%~80 mol%)均具有热致液晶行为.当复合物中共聚酯含量≤50 wt%以及共聚酯中对羟基苯甲酸(HB)含量≤60 mol%时,共聚酯分子的结构更加均匀化,结晶组分的结晶行为受到限制,基体与液晶组分具有较好的复合效果,不表现明显的相分离行为.复合物与相应的纯共聚酯相比,具有较好的热稳定性;其粘度均比基体PBT-PTMG小.当复合物中共聚酯含量≥30 wt%时,其粘度下降尤为显著,表明其具有较好的加工性.

PREPARATION AND PROPERTIES OF COMPOSITES OF THERMOTROPIC LIQUID CRYSTALLINE COPOLYESTERS AND POLYESTER THERMOPLASTIC ELASTOMER

The composites of thermotropic liquid crystalline copolyesters((p-hydroxy benzoic acid)-terephthalic acid-resorcin)(HB-TA-RES) and poly(butylene terephthalate)-poly(tetramethylene glycol) thermoplastic elastomer(PBT-PTMG) with different copolyester content or copolyester composition were prepared by in-situ polycondensation method.The obtained(HB-TA-RES)/PBT-PTMG were characterized by POM,TGA,WAXD,SEM and rheological analysis.Liquid crystalline behavior of the composites was observed when the HB content in copolyester was 40 mol% and copolyester content in composite was 30?wt%～70?wt% or copolyester content in composite was around 50?wt% and HB content in copolyester was 20 mol%～80 mol%.When the copolyester content in composites ≤50?wt% or HB content in copolyester≤60 mol%,no obvious phase separation happened.The molecular structure of copolyester in composites was more homogeneous and the crystallization of HB was limited.The good thermal stability of(HB-TA-RES)/PBT-PTMG composites with thermotropic liquid crystalline behavior was obtained as compared with the corresponding homocopolyester and the viscosity of the composites was lower than that of the matrix PBT-PTMG especially when the copolyester content was more than 30?wt%.Good processability of the composite is expected in the application.