【聚偏氟乙烯论文：nips法制备超疏水性pvdf膜的研究】.doc

聚偏氟乙烯论文：NIPS法制备超疏水性PVDF膜的研究 【中文摘要】本文研究了以TEP-DMAc为混合溶剂,利用非溶剂相转化法(NIPS)制备PVDF微孔分离膜的方法。其中涉及了PVDF种类、聚四氟乙烯(PTFE)颗粒、异丙醇凝胶浴以及以无纺布为支撑体对PVDF微孔膜的影响。具体结果如下：首先,比较了由PVDF和PVDF-HFP两种膜材料所制备的微孔膜的分离性能、疏水性能、机械性能等各方面的膜性能,通过实验数据说明,在相同的制膜条件下,PVDF微孔膜的膜性能在各方面均优于PVDF-HFP微孔膜。其次,讨论了纳米级的PTFE颗粒以及异丙醇凝胶浴对于PVDF-PTFE微孔膜的影响。其中,PTFE颗粒负载量的提高有利于PVDF-PTFE微孔膜的疏水性能的提高,上下表面初始动态接触角分别由79°和112°增加到了85°和131.5°。同时,膜结构也从不对称的指状孔和海绵状的双面结构变化成为伴有团聚结构的海绵状对称的膜结构。以异丙醇为凝胶浴所制备的PVDF-PTFE微孔膜在疏水性方面得到了进一步的提高,初始动态接触角由87°增加到130°以上,但同时其对应的微孔膜机械强度也出现了大幅度下降。实验数据表明,以浓度为80wt.%的异丙醇为凝胶浴,在其中停留5秒钟后转入纯水凝胶浴中充分凝胶所制备的PVDF-PTFE微孔膜的各项膜性能最为理想。最后,本文还考察了以无纺布为支撑体的PVDF-PTFE微孔膜的各项膜性能的变化情况。其微孔膜的上下表面初始动态接触角基本保持在120°到130°,并且在经过温度为60℃烘箱热处理过之后,初始动态接触角可以提高5°左右。 【英文摘要】With mixture of triethyl phosphate (TEP)-N, N-dimethylacetamide (DMAc) solvent, the flat microporous hydrophobic membranes were prepared using nonsolvent induces phase separation (NIPS) method. Many factors which could influence the performance of microporous hydrophobic membranes were studied, such as different kinds of polyvinylidene (PVDF), polytetrafluoroethylene (PTFE) particles, coagulation bath of isopropanol and non-woven fabrics as membrane support. The experimental results are as following:Firstly, the differences between PVDF and PVDF-HFP microporous membrane in membrane performance, hydrophobicity and mechanism were studied. Based on the result of experiment, the performance of PVDF membrane was better than PVDF-HFP membrane.Secondly, the introduction of PTFE particles could improve the hydrophobicity of PVDF-PTFE membrane, with the increase of dynamic contact angle (up side and down side of membrane) from 79°and 112°to 85°and 131.5°. And at the same time the morphology of membrane changed from finger-like and sponge-like structure to sponge-like structure across the whole section. Additionally, isopropanol coagulation could also improve the membrane hydrophobicity greatly from 87°to more than 130°. Base on the experiment, the ideal membrane could be prepared with 50wt.% PTFE par