PVC/PSf共混相容性及其对膜结构和性能的影响

COMPATIBILITY OF PVC/PSf MIXING AND ITS EFFECT ON THE STRUCTURES AND PERFORMANCES OF ALLOY MEMBRANES

本文通过混合焓法预测并用差示扫描量热法表征了PVC/PSf共混体系的相容性,表明二者为部分相容体系。以Flory-Huggins的高分子溶液理论为基础,通过Wood方程,计算出了不同共混比的PVC/PSf共混体系两相中二组分的表观体积分率,进而计算出体系的聚合物-聚合物相互作用参数X1,2对PVC/PSf共混体系的相容性进行了校验。通过对不同共混比的膜结构和性能的考察,结果表明:共混膜中聚合物的共混比影响PVC/PSf的相容性,进而影响共混膜的结构和性能;当聚合物浓度为17%,PVC/PSf共混比为4:1时,所制得的PVC/PSf共混中空纤维膜具有较高的水通量和截留率。

The compatibility of PVC/PSf mixing was predicted by mixing enthalpy and characterized by Differential Scanning Calorimetry. It was indicated that the system of the both was partially compatible. From the measured glass transition temperature, apparent volume fractions of PVC and PSf components in the PVC-rich phase and PSf-rich phase of PVC/PSfblends were calculated by Wood relation, and Flory-Higgins polymer-polymer interaction parameter were determined. Apart from the above experiments, the structures and performances of PVC/PSf alloy membranes with different PVC/PSF ratio were studied. The results demonstrated that PVC/PSfblends was a partial-compatibility system, and the compatibility was influenced by the ratio of PVC to PSf in their blends and so did the structuras, and performances of alloy membranes.