超高分子量聚乙烯微孔材料微观结构形成机理的研究 (I)相分离过程对微观结构的影响

Microstructure Formation Mechanism of Microporous UHMWPE (I)Effect of phase separation on microstructure

超高分子量聚乙烯（ＵＨＭＷＰＥ）微孔材料是以ＵＨＭＷＰＥ为聚合物基体的一种新型功能性材料，利用这种材料能够实现非均相分离、过滤及离子通透等多种单元操作过程，可广泛地应用于化工、医药、能源等领域［１］。针对ＵＨＭＷＰＥ物料的特殊性能，采用热致相分离方法［２］（ＴＩＰＳ）进行微孔材料的成型。ＴＩＰＳ过程涉及到聚合物－溶剂二元体系，因此对ＴＩＰＳ的二元体系热力学过程进行了研究。同时，二元体系的相分离过程对微观结构有很大影响。结合ＵＨＭＷＰＥ－石蜡油二元体系相图可以知道，该二元体系的相分离由两种不同的相分离过程组成———固液相分离和液液相分离，研究了两种分离过程对最终微观结构的影响。

Microporous ultra high molecular weight polyethylene (UHMWPE)is a new type of functional material based on UHMWPE,it can be used for heterogeneous phase separation and filtration etc.It is formed by thermally induced phase separation (TIPS).TIPS is concerned with polymer diluent binary system.The thermodanamic process of TIPS of UHMWPE and mineral oil system is observed.It is noted that the phase separation of the two components has great effects on the resulting structure of microporous UHMWPE.Seen from the phase diagram of the binary system,TIPS involves solidliquid and liquidliquid phase separation.