iPP/EPR共混物的动态流变行为与相容性

摘要

The dynamic rheological behavior of isotactic polypropylene (iPP)/ethylene-propylene random copolymer (EPR)blends was investigated by rotational rheometer under the molten state. The effects of the mass fraction of EPR,temperature and angular frequency on the dynamic rheo-logical behavior of the blends were discussed,and the melting miscibility was analyzed.The re-sults show that the complex viscosities of the melt of iPP,EPR and the blends reduce with the angular frequency increasing,indicating of shear-thinning behavior of pseudoplastic fluid.The varia-tion of zero shear viscosity of iPP/EPR blends shows positive-negative devitions with the mass fraction of EPR increasing and the viscosity-composition curve reveals an S shape.The zero shear viscosity shows negative deviation when the mass fraction of EPR is less than 18%,whereas the positive deviation occurs when the mass fraction of EPR is 18%~30%.The melt of iPP/EPR blends at different temperatures is all homogeneous,which means that they have good miscibility.%使用旋转流变仪研究了等规聚丙烯(iPP)/乙烯-丙烯无规共聚物(EPR)共混物在熔融状态下的动态流变行为,探讨了共混物的动态流变行为随EPR的质量分数、温度以及角频率的变化规律,分析了共混物的相容性。结果表明：随着角频率的增加,iPP,EPR以及iPP/EPR共混物熔体的复数黏度呈下降趋势,呈现出假塑性流体的剪切变稀行为。iPP/EPR 共混物的零剪切黏度随着EPR加入量的变化出现了正-负偏差,曲线呈S形。当EPR的质量分数小于18%时,零剪切黏度出现负偏差,而当EPR的质量分数在18%~30%时出现正偏差。不同温度下的iPP/EPR共混物熔体为均相结构,iPP与EPR之间具有一定的相容性。