【摘要】 为研究高压条件下聚合物的流变性能,以熔融共混挤出的方法制备聚对苯二甲酸乙二醇酯-聚酰胺6嵌段共聚物(PET-PA6)与聚酰胺6(PA6)共混物,利用安装在反向压力腔末端的旋塞控制毛细管出口压力,研究该共混物在出口压力为5～50 MPa条件下,剪切速率和温度对PET-PA6/PA6共混物流变行为的影响。结果表明:PET-PA6/PA6共混物的剪切黏度随压力的变化规律符合Barus方程;在恒定剪切速率下,随着毛细管内平均压力的增加,剪切黏度逐渐增大;当剪切速率从108 s-1增加到1 080 s-1时,压力系数减小19. 24%,当温度从265℃增加到290℃时,压力系数减小32. 33%,共混物熔体剪切黏度对压力的依赖性随剪切速率和温度的增加逐渐减小。更多还原

【Abstract】 In order to study the rheological properties of polymers under high pressure,blends of polyethylene terephthalate-polyamide 6 copolymer（ PET-PA6） and polyamide 6（ PA6） were prepared by melt blending and co-extruding. The influence of pressure,shear rate and temperature on the rheological behavior of PET-PA6/PA6 blends were studied under the conditions of the outlet pressure of the capillary tube of 5-50 MPa controlled by a cock mounted at the end of the reverse pressure chamber. The results indicate that the shear viscosity of PET-PA6/PA6 blends conforms to the Barus equation with the change of pressure. At a constant shear rate,the shear viscosity of PET-PA6/PA6 blends increases gradually with the capillary pressure. When the shear rate is increased from 108 s^-1 to 1 080 s^-1,the pressure coefficient decreases by 19. 24%,and when the temperature is increased from 265 to 290 ℃,the pressure coefficient decreases by 32. 33%. The dependence of shear viscosity of PET-PA6/PA6 blends on pressure decreases with the shear rate and the temperature.更多还原