【摘要】 采用少量高分子量聚乙烯(HMWPE)在动态保压剪切应力场中诱导中等分子量聚乙烯(MMWPE),在这种双重诱导的作用下得到了性能良好的聚乙烯材料,其平行于流动方向的拉伸强度和冲击强度达到了71.17 MPa和75.79 kJ/m2,分别提高了209.4%和252.8%;通过差示扫描量热(DSC),X射线衍射(WAXD)和扫描电镜(SEM)对其增强增韧的机理进行了探讨,实验表明,在振动压力为8.5 PMa,熔体温度为180℃时,剪切层的结晶度达到了65.7%,且具有最高的晶面衍射强度,并从SEM照片可以证明,确实生成了类似网状的shish-kebab结构。更多还原

【Abstract】 High density polyethylene was induced by small amount of high-molecular-weight polyethylene(HMWPE) and shear-stress produced by dynamic packing injection molding.The experiment substantiates that the further improvement of tensile strength along the flow direction of high-density polyethylene(HDPE)/HMWPE samples is achieved and the value is 71.17 MPa,whereas the impact strength still substantially exceeds that of conventional molding and the value is 75.79 kJ/m2.For further to discuss the mechanism of this high strength and toughness,the obtained samples were characterized via differential scanning calorimetry(DSC),wide angle X-ray diffraction(WAXD) and scanning electron microscope(SEM).The experimental results show that the shish-kebab structure which is composed of stretched chains(shish) and lamellae(kebab) is seen in the oriented region of samples.The degree of crystallinity in shear region which is approved by DSC and SEM is 65.7%,at the same time,it can been seen the net shish-kebab by SEM.更多还原