矿脂对UHMWPE的结晶和流变行为的影响

使用矿脂作为新型溶剂溶胀超高摩尔质量聚乙烯(UHMWPE),利用熔融共混制备了不同矿脂含量的UHMWPE/矿脂凝胶,通过扫描电子显微镜、示差扫描量热分析仪和流变仪测试分析了矿脂含量的不同对凝胶体系的形貌、结晶行为和流变行为的影响。结果表明,矿脂含量的增加可提高UHMWPE分子链网络的溶胀水平,减少链间缠结,增加自由链数量,进而UHMWPE体系的弹性模量减小,结晶速率加快,加工性能提高。In this study,petrolatum was used as a novel solvent to swell ultra-high-molecular-weight polyethylene( UHMWPE) to prepare UHMWPE / petrolatum gels with different petrolatum concentrations by melt blending. The morphology,crystallization and rheological behaviors of the UHMWPE / petrolatum gels were investigated by scanning electron microscope, differential scanning calorimetry and rheometer. The experimental results reveal that the increase of petrolatum concentration improves the swelling level of the molecular chain networks, reduces the molecular chain entanglements and increases the amount of free molecular chains of UHMWPE. In this case, the elastic modulus is decreased, the crystallization rate is accelerated,and the processability of UHMWPE is improved.