【摘要】 线性聚乙烯熔体的强异常流动行为源于其分子量高、分子链缠结点多、熔体的界面吸附性强。用聚合填充法制备的 UHMWPE/ kaolin和 HDPE/ kaolin体系可以顺利地由毛细管挤出 ,且填充量增大 ,体系表观粘度下降 ,加工流动性变好。分析表明 ,在滑动动力学边界条件下 ,管壁附近的熔体承受的真实剪切速率和剪应力减少。管壁处粘性作用的下降 (脱附 )和物料实际承受的弹性变形能减少 ,是第二光滑区中获得稳定滑动流动的重要条件。更多还原

【Abstract】 The extreme flow behaviors of linear PE melts are caused by the high molecular weight, more entanglements and strong adsorption of melt at capillary wall. UHMWPE/kaolin and HDPE/kaolin prepared by polymerization filling can be smoothly extruded through capillary, and with increasing addition of kaolin the apparent viscosity of the composite is decreased and the processability is improved. Under slip border condition the real shear rate and shear stress of the melts near the wall are decreased. The viscosity descent and the deformation energy decrease of the melt near the wall are the important conditions to gain steady flow in the second glossy zone.更多还原