超高分子量聚乙烯树脂颗粒形态与结构性能的关系

Relationship Between Particle Morphology and Structure,Properties of Ultra-High Molecular Weight Polyethylene Resin

比较不同聚合工艺制备的2类超高分子量聚乙烯(UHMWPE)树脂的差异,利用扫描电镜、热台显微镜、旋转流变仪、差示扫描量热分析、高温乌氏黏度计等研究了树脂的颗粒形态与其结构和性能之间的关系。结果表明,经预聚合工艺制得的树脂颗粒致密、规整、球形度高,且颗粒粒径与相对分子质量呈正相关关系,同时粒径越大,UHMWPE/白油体系的黏度越大;未经预聚合工艺制得的树脂颗粒表面凹凸不平,树脂在白油中出现分裂现象,且升温过程中黏度出现波动,其颗粒粒径与相对分子质量或黏度不存在相关性。

Two kinds of UHMWPE resin with different particle morphologies were obtained through different polymerization processes.And SEM,hot stage microscope,rotary rheometer,DSC,high temperature Ubbelohde viscometer were used to study the structure and properties of UHMWPE resins.The results show that the resin particles after prepolymerization are dense,regular,and spherical,and the particle size is positively correlated with the molecular weight.And the larger the particle size is,the greater the viscosity of the UHMWPE/white oil systems is.The surface of resin particles without prepolymerization is uneven and split in white oil;the viscosity will fluctuate during the heating process,and there is no correlation between the particle size and molecular weight or the viscosity of the UHMWPE/white oil systems.