压力对不同特性黏度聚酯流变行为的影响  

Effects of hydrostatic pressure on rheological behavior of PET with different intrinsic viscosity

作　　者：唐兵兵[1,2] 李健[2] 郭增革[1,2] 甘丽华[1,2] 李鑫[2] 

机构地区：[1]天津工业大学材料科学与工程学院,天津300387 [2]中国纺织科学研究院生物源纤维制造技术国家重点实验室,北京100025

出　　处：《纺织学报》2015年第6期13-17,共5页Journal of Textile Research

基　　金：国家"十二五"科技支撑计划资助项目(2011BAE05B00)

摘　　要：采用毛细管流变仪及其配套的反向压力腔组件控制毛细管出口压力,在平均压力为5~50 MPa下研究了3种不同特性黏度的聚酯（PET）的流变行为。结果表明：PET的剪切黏度随着平均压力的增大都呈指数增加,符合Barus方程。压力系数随着特性黏度的增大而减小,当特性黏度由0.48增加至0.67 d L/g时,压力系数显著减小,且这种变化随着剪切速率的增大而衰减,当特性黏度≥0.67 d L/g时,压力系数随剪切速率的变化不大。压力系数随剪切速率的增大而减小,特性黏度为0.48 d L/g时变化显著,当特性黏度≥0.67 d L/g时,压力系数随剪切速率的变化不大。压力系数随着温度的升高而减小,且变化率随着温度的升高显著减小。不同特性黏度PET压力系数的变化表明,特性黏度较低时,自由体积较大,表现在玻璃化转变温度低,受压力的影响显著;当特性黏度为0.67和1.00 d L/g时,自由体积的减小不再明显,因此受压力的影响也不再明显。The effects of hydrostatic pressure on the rheological behavior of PET with different intrinsic viscosities were studied using a capillary rheometer and its matched eounterpressure chamber to control the pressure of capillary outlet in an average pressure average pressure of 5 - 50 MPa. The results indicated that the shear viscosity of PET exponentially increased with increasing average pressure, conforming to the Barus equation. The pressure coefficient decreased with increasing intrinsic viscosity, when the intrinsic viscosity increased from 0.48 to 0.67 dL/g, the press coefficient decreased significantly, and this change with the increase in the shear rate was attenuated. When intrinsic viscosity ≥ 0. 67 dL/g, the press coefficient changed slightly with intrinsic viscosity. The press coefficient decreased with increasing the shear rate. When the intrinsic viscosity was 0. 48 dL/g, the change was significant; however, intrinsic viscosity ≥0. 67 dL/g, the press coefficient changed slightly. The press coefficient decreased with increasing temperature and the change rate decreased significantly with increasing temperature. The changes in Press coefficient of PET in different intrinsic viscosity indicated that when the intrinsic viscosity and the glass transition temperature was low, the affect of pressure on press coefficient was significantly. When the intrinsic viscosity were O. 67 and 1. O0 dL/g, the decrease of the free volume were no longer obvious, therefore the affect of pressure on press coefficient were insignificant.

关 键 词：聚酯 压力系数 特性黏度 流变行为 

分 类 号：TQ311[化学工程—高聚物工业]