【摘要】 首次提出一种制备有机-无机杂化膜的新方法,即将正硅酸乙酯(TEOS)直接添加到聚偏氟乙烯(PVDF)铸膜液中,在入水凝胶时,PVDF逐渐固化成膜,而TEOS同时也与水发生水解聚合反应,生成硅氧聚合物,这就为形成无机高分子与PVDF互穿网络结构或分子链相互缠绕创造了机遇,为制备力学性能优良的聚偏氟乙烯-硅杂化膜提供了可能.实验初步考察了正硅酸乙酯的添加量对聚偏氟乙烯-硅杂化膜的超滤性能和力学性能的影响,对杂化膜进行了能谱分析.结果表明:1)能谱实验证明杂化膜表面有Si元素存在,表明TEOS在凝胶过程中发生水解聚合反应,生成硅氧聚合物留在杂化膜中;2)在无致孔添加剂存在时,随TEOS添加量的增加,杂化膜的纯水通量增大,而对牛血清蛋白的截留率呈现持续下降的趋势;当TEOS含量为8%时,与无TEOS的PVDF膜相比,杂化膜的拉伸强度σt和弹性模量E几乎增加一倍;3)在有致孔添加剂PVP K30和无水LiCl存在时,杂化膜的纯水通量随TEOS添加量的增加呈先升后降然后再上升的趋势,对牛血清蛋白的截留率呈现持续下降的趋势.当TEOS添加量为12%时,与无TEOS的PVDF膜相比,超滤性能相近,但杂化膜的拉伸强度tσ和弹性模量E增加近一倍.更多还原

【Abstract】 A new method to prepare hybrid membranes was first presented in this paper.Tetraethyl orthosilicate(TEOS) is directly added into the polyvinylidene fluoride(PVDF) casting solution.During the membrane coagulation in water,the TEOS in casting solution was hydrolyzed and polymerized,and a silicon-oxygen polymer was formed.Under an appropriate condition the entanglement or interpenetrating structure between silicon-oxygen polymer and PVDF chains may be got,which is benefit to the mechanical performance of hybrid membrane.Element analysis shows that Si exists on the surface of hybrid membrane when TEOS content is not too low.The effects of TEOS content on the performance of hybrid membranes were investigated.The results show that the pure water fluxes increase and the retentions of BSA decrease with TEOS content increase for the hybrid membrane without additives.When TEOS content was 8%,the tensile strength and elastic modulus of hybrid membrane were about twice of that of the PVDF membrane without TEOS addition.For the hybrid membranes prepared with PVP and LiCl additives,the pure water fluxes decreased first,then increased and the retention of BSA decreased with TEOS content increase.When TEOS content was about 12%,the ultrafiltration performances of hybrid membrane and PVDF membrane without TEOS addition were the same,but the tensile strength and elastic modulus of hybrid membrane were almost twice of that of the PVDF membrane without TEOS addition.更多还原