有机硅烷改性沸石/PDMS渗透汽化杂化膜的制备及表征

Preparation and characterization of silane modified PDMS/silicalite hybrid membrane

采用硅烷偶联剂,乙烯基三甲氧基硅烷(VTMS)为改性剂,控制改性时间(4h和12h),对全硅沸石进行改性,以聚二甲基硅氧烷(PDMS)为基体,制备了改性沸石填充的PDMS渗透汽化杂化膜。用X射线衍射(XRD)、扫描电子显微镜(SEM)、傅立叶变换红外光谱(FT-IR)、热重分析(TGA)、机械拉伸等手段对改性的效果和杂化膜的热稳定性能进行了表征,结果表明改性后沸石晶型未改变,杂化膜热稳定性和机械性能提高。并以乙醇质量分数为5%的乙醇/水体系为研究对象,分离因子为评价指标,考察了改性杂化膜对乙醇的分离性能,结果表明膜对乙醇/水的分离因子可由未改性时的16提高至29.5,这说明采用硅烷偶联剂对沸石进行改性是提高膜分离性能的有效方法。

Surface-modified silicalite-1-filled polydimethylsiloxane（PDMS） ethanol permselective pervaporation membranes were prepared by incorporating different silane coupling agent modified silicalite-1 particles,4 hours and 12 hours,into PDMS.The modification effects,the thermal resistant performance and the mechanical performance of the hybrid membrane were investigated by XRD,SEM,FT-IR,TGA and tensile experiment.The results showed that the modification of silicalite-1 did not influence the framework of silicalite-1 crystals,and the thermal stability and mechanical property were improved.Selectivity of hybrid membranes for 5%（wt%）ethanol-water system was measured,results revealed that separation factor of hybrid membranes can be improved to as high as 29.5.Pervaporation performance of hybrid membranes was greatly enhanced by modification.