聚乙烯醇衍生的聚离子复合物的研究——Ⅳ.聚离子复合物膜的力学行为及透过性能

POLYIONIC COMPLEXES DERIVED FROM POLYVINYL ALCOHOL IV. MECHANICAL BEHAVIOR AND PERMEABILITY OF POLYIONIC COMPLEXES MEMBRANES PREPARED FROM PVA AND ETHYLENE-VINYL ALCOHOL COPOLYMER

聚离子复合物(PICs)膜对水、小分子电解质和低分子物质具有很高的透过性,而高分子物质则不易通透,因此,作为血液透析用的半透膜而受到很高的评价。

The mechanical behavior of polyionic complex (PIC)membranes derived from polyvinyl alcohol(PVA) or ethylene-vinyl alcohol copolymer (EVA) have been investigated. The presence of ethylene block segment in the backbone of polyions can endow PIC membranes with more toughness. Increasing the degree of substitution of the polyions, the formed PIC becomes harder and more brittle. Under the environment of relative humidity (R. H. ) of 40%, the tensile strength, relative elongation and modulus of PICs are at about 300 kg/cm2, 10% and 8×103 kg/cm2, respectively, whereas in the environment of 90% R. H. , these of PICs derived from EVA are at about 90 kg/cm2, 150% and 13 kg/cm2, respectively, better than that of PVA derived polyionic membrane and ordinary PIC such as loplex 101. The permeability of PIC membranes derived from EVA have also been studied.