摘要
通过表面涂覆法制备聚偏氟乙烯(PVDF)/有机硅疏水复合膜.实验将聚二甲基硅氧烷(PDMS)、正硅酸乙酯(TEOS)及催化剂二丁基二月桂酸锡按一定比例混合,涂于聚偏氟乙烯中空纤维膜基膜表面并固化交联,研究和讨论影响涂层效果的主要因素,得到正交实验的最优因子组合,使改性后的膜丝具有较好的性能.结果表明:在正己烷/聚二甲基硅氧烷/正硅酸乙酯/催化剂体系中,正硅酸乙酯含量是影响膜蒸馏水通量的主要因素;聚二甲基硅氧烷含量对膜的透气系数的影响最大,浸泡时间主要影响膜的疏水性.优化的疏水涂层条件为:m(聚二甲基硅氧烷)∶m(正硅酸乙酯)∶m(催化剂)=10∶2∶1(质量比),涂层温度28℃,浸泡时间20s.测试结果显示,有机硅涂敷后聚偏氟乙烯膜的表面静态接触角从83°提高到116°,且膜蒸馏通量保持率达90%以上,通量随运行时间延长的衰减情况得到改善.
Polydimethylsiloxane （PDMS）, tetraethyl orthosilicate （TEOS） and dibutyl tin dilaurate （DBTDL） catalyst were employed as surface coating agents on polyvinylidene fluoride（PVDF） hollow fiber membrane to prepare PVDF/organosilicon hydrophobic composite membrane. Through systematic experiments, coating formulations and process parameters were optimized. The results showed that the membrane distillation（MD） flux was mainly determined by the TEOS content, and the permeability coefficient was greatly affected by the PDMS portion, while the membrane contact angle was depended on the soaking time. With optimized portions and conditions of m（PDMS） 10 ： m（TEOS） 2 ： m（DBTDL）I （mass ratio） under coating temperature 28 ℃ and soaking time 20 s, the modified composite membrane shows improved MI） flux running time loss and hydrophobic property（contact angle from 83°to 116°）, as well as a good flux retention rate.
出处
《膜科学与技术》
CAS
CSCD
北大核心
2016年第4期30-37,共8页
Membrane Science and Technology
关键词
表面涂敷
聚二甲基硅氧烷
聚偏氟乙烯
正交实验
膜蒸馏
surface coating
polydimethylsiloxane
polyvinylidene fluoride
orthogonal design
membrane distillation
