茂金属聚乙烯(MPE)/线性低密度聚乙烯(LLDPE)共混熔体的流变学

Rheology of Melt of Metallocene Polyethylene/Linear Low Density Polyethylene Blends

研究了不同比例共混的茂金属聚乙烯 (MPE)和线性低密度聚乙烯 (LLDPE)熔体的流变学行为 ,讨论了共混物组成、剪切速率和剪切应力以及温度对熔体流变曲线、熔体粘度的影响 ,为MPE的共混改性提供了理论依据。结果表明 :随着LLDPE含量的增加 ,共混熔体的粘度降低 ,转变应力和非牛顿指数减小 ,粘流活化能升高 ,MPE的流动性和加工性能得到改善。

Rheological behavior of melts of metallocene polyethylene(MPE)/linear low density polyethylene(LLDPE) blends with different proportions is studied.Influences of compositions of the blends,shear ratio and shear stress on rheogram and melt viscosity are discussed,providing theory basis to MPE blending modification.Results show that the viscosity,stress and non-Newtonian index of the blend melt decrease with the increase of LLDPE contents,but the viscous flow activation energy of it increases.The flowability and processability of MPE are improved.