熔纺PU/PVDF共混中空纤维膜研究

Study on polyurethane/polyvinylidene fluoride blend hollow fiber membrane prepared by melt spinning

以聚氨酯(PU)与聚偏氟乙烯(PVDF)共混,经熔体纺丝及后拉伸得到具有聚合物界面微孔的中空纤维膜。分析PU/PVDF的混溶性,讨论膜孔结构的形成,并对其形貌进行观察。结果表明,随PU/PVDF混溶性的改善,共混物可纺性提高,成孔性则有所下降;拉伸使膜界面微孔张开,随拉伸倍数的增加膜通量先增加再略有下降后迅速增加,共混物晶区的规整性也有所提高;所得膜为对称结构,且高倍拉伸后膜表面形成大量界面微孔。

Using melt spinning technology, polyurethane/polyvinylidene fluoride （PU/PVDF） blend was spun into hollow fiber membranes with interfacial micro-voids. The miscibility of PU and PVDF was analyzed. The pore formation of the membrane was discussed, and the morphology of the membrane was also observed. Results showed that with the improvement of the miscibility of PU and PVDF, the spinnability of the blend increased, but the pore formation property decreased. The interracial micro-voids were opened by drawing, and with the increase in draw ratio, the water flux increased, then decreased and followed by fast increasing and the aggregation of the blend also became more regular. The structure of the membrane obtained was symmetrical and there were many interfacial micro-voids on the surface of the membrane with high draw ratio.