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从分子设计理论出发提出了对PVDF超滤膜复合改性模型。该模型在纳米粒子疏水改性的基础上接枝亲水链,该亲水链促使复合粒子在凝胶成膜过程中大量离析富集在膜(孔)表面,增强膜的亲水性。在该模型指导下的试验研究表明:在截留率基本保持不变的情况下,1#膜水通量是114.2L/(m2·h),水接触角是62.1°,而2#膜水通量提高到193.5L/(m2·h),水接触角下降到43.5°;SEM观察2#膜较1#膜表面更致密,而膜断面指状孔减少,海绵层变厚;XPS表明2#膜较1#膜表面O/F值从0.08提高到0.20,除了C、O、F元素,还增加Ti元素,这解释了纳米粒子的表面离析富集现象;1#膜和2#膜压密性无显著差异。试验在一定程度上验证了该模型的正确性。
Based on the theory of molecular design, a modified composite model of PVDF membrane was proposed. The model grafts the hydrophilic chains on the basis of the hydrophobic modification of the nanoparticles. The hydrophilic chains promote the separation and enrichment of the composite particles on the membrane (pore) surface during the process of gel formation and enhance the hydrophilicity of the membrane. Under the guidance of this model, experimental studies show that the water flux of membrane # 1 is 114.2L / (m2 · h) and the water contact angle is 62.1 ° while the rejection rate remains basically unchanged. And the water contact angle decreased to 43.5 °. SEM observation showed that the thickness of # 2 film was more dense than that of film # 1 while the number of finger-like pores was reduced and the thickness of sponge layer was thicker. The XPS value of 2 # The O / F value of the surface of the membrane was increased from 0.08 to 0.20 compared with that of the membrane # 1, and the Ti element was also added in addition to the elements C, O and F, which explained the segregation and enrichment of the surface of the nanoparticles; No significant difference in sex. Test to a certain extent, verify the correctness of the model.