聚（乙烯醇）/1,2-双（三乙氧基硅基）乙烷新型有机-无机杂化膜的表征与渗透性能

Characterization and permeation performance of novel organic-inorganic hybrid membranes of poly(vinyl alcohol)/1,2-bis(triethoxysilyl)ethane.

作者信息

Zhang Qiu Gen, Liu Qing Lin, Zhu Ai Mei, Xiong Ying, Zhang Xiu Hua

机构信息

Department of Chemical and Biochemical Engineering, National Engineering Laboratory for Green and Chemical Productions of Alcohols, Ethers, and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, PR China.

出版信息

J Phys Chem B. 2008 Dec 25;112(51):16559-65. doi: 10.1021/jp807573g.

DOI:10.1021/jp807573g

PMID:19367893

Abstract

Bis(trialkylsilyl) precursor was used to modify polymer membranes for the first time. Novel organic-inorganic hybrid membranes of poly(vinyl alcohol) (PVA)/1,2-bis(triethoxysilyl)ethane (BTEE) were prepared through a sol-gel method for pervaporation dehydration of ethanol. The permeability and selectivity of the membranes were improved simultaneously. The physicochemical properties of the hybrid membranes were investigated. With increasing BTEE content, the amorphous region in the hybrid membranes increased and became more compact. Phase separation took place in the hybrid membranes containing abundant BTEE, and silica particles distributed in the PVA matrix homogeneously. Compared to PVA membranes, the hybrid membranes exhibit high thermal stability and improved separation performances. Silica-hybrids reduced significantly the swelling of PVA membranes in an aqueous solution. The Flory-Huggins interaction parameter of water with membranes chi13 increased with increasing BTEE content, whereas that of ethanol with membranes chi23 decreased. Diffusion behavior of water and ethanol through the membranes were analyzed using the Maxwell-Stefan equation. When BTEE content was below 6 wt%, diffusion coefficient of water D13 increased remarkably and that of ethanol D23 decreased slightly.

摘要

首次使用双（三烷基硅基）前驱体对聚合物膜进行改性。通过溶胶-凝胶法制备了新型聚（乙烯醇）（PVA）/1,2-双（三乙氧基硅基）乙烷（BTEE）有机-无机杂化膜用于乙醇渗透汽化脱水。膜的渗透率和选择性同时得到提高。对杂化膜的物理化学性质进行了研究。随着BTEE含量的增加，杂化膜中的无定形区域增加且变得更加致密。在含有大量BTEE的杂化膜中发生了相分离，二氧化硅颗粒均匀地分布在PVA基质中。与PVA膜相比，杂化膜表现出高的热稳定性和改善的分离性能。二氧化硅杂化物显著降低了PVA膜在水溶液中的溶胀。水与膜的Flory-Huggins相互作用参数χ13随着BTEE含量的增加而增加，而乙醇与膜的相互作用参数χ23则降低。使用Maxwell-Stefan方程分析了水和乙醇在膜中的扩散行为。当BTEE含量低于6 wt%时，水的扩散系数D13显著增加，而乙醇的扩散系数D23略有下降。