填充法改性PDMS膜及其对乙酸/水的渗透汽化分离性能

用CTAB-蒙脱石填充改性PDMS膜，运用XRD, SEM等手段表征了不同填充量的复合膜结构，证明有机柱撑蒙脱石与聚合物形成插层型复合物后，膜的热稳定性明显改善. 研究了填充膜对乙酸/水体系的渗透汽化分离性能，结果表明，随着温度的升高，渗透通量增大而分离因子降低，通量随填充量增加单调上升，分离因子随填充量增加先增大后降低，填充量为7.4(%, w)时达到最大值. 从膜的结构及其与组分的相互作用对填充膜中蒙脱石可能存在的渗透通道作用进行了探讨.

Modification of PDMS Membrane by Organo-montmorillonite for Pervaporation of Acetic Acid over Water

An organo-montmorillonite filled polydimethylsiloxane membrane was developed for recovering acetic acid from its dilute solution by pervaporation. The filled membrane was prepared by cross linking reaction in solution using cetyltrimethylammonium bromide (CTAB) pillared montmorillonite. XRD and SEM were applied to characterize the filled membrane morphology. The results showed that the filled membrane with organoclay silicate layers not only showed the most optimal thermal stability but also exhibited the highest separation factor for the pervaporation of acetic acid over water when the filler content was around 7.4%(w). A possible mechanism was proposed that the enhanced selectivity and permeability were derived from the effect of permeable reactive passageways for adsorption-transport-desorption because of the ordered nano-layered structure and hydrophobic capacity of organo-montmorillonite in the hybrid membrane.