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用Ｉｎｓｔｒｏｎ３２１１型毛细管流变仪研究了以对羟基苯甲酸（ＰＨＢ）、对苯二甲酸（ＴＰＡ）和双酚Ａ（ＢＰＡ）为单体合成的共聚芳酯液晶熔体的流变性能。结果表明，切变速率、熔体温度及ＰＨＢ链节含量对切粘度和结构粘度有很大的影响。切变速率在１０～１０３／Ｓ、温度２９５～３３０℃范围内，共聚酯粘流活化能△Ｅη为７４．５～２０５．１（ｋＪ／ｍｏｌ）。液晶熔体在剪切流中存在屈服应力τｏ，随温度升高τｏ值降低。在低温、低切变速率下，共聚酯熔体的弹性很小，甚至呈现挤出收缩现象。
The rheological properties of liquid crystalline copolyester copolyesters synthesized from p-hydroxybenzoic acid (PHB), terephthalic acid (TPA) and bisphenol A (BPA) were investigated by using Instron3211 capillary rheometer. The results show that the shear rate, the melt temperature and the content of PHB link have a great influence on the shear viscosity and the structural viscosity. The shear rate △ Eη of viscous flow of copolyester was in the range of 10 ~ 103 / S and temperature of 295 ~ 330 ℃, which was 74.5 ~ 205.1 (kJ / mol). Liquid crystal melt yield stress in the shear flow τo, with the temperature increase τo value decreases. At low temperature, low shear rate, the melt elasticity of the copolyester is small and even shows extrusion shrinkage.