溶胀法改性聚二甲基硅氧烷及在多层复合膜中的应用  

Modification of PDMS by swelling method and its application in multilayer composite membranes

作　　者：高继发 赵丹[2] 孙健[2] 陈淑慧 任吉中[2] 马君玲[1] GAO Jifa;ZHAO Dan;SUN Jian;CHEN Shuhui;REN Jizhong;MA Junling(School of Environment and Chemical Engineering,Dalian Jiaotong University,Dalian 116028,China;National Laboratory for Clean Energy,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,China)

机构地区：[1]大连交通大学环境与化学工程学院,大连116028 [2]洁净能源国家实验室,中国科学院大连化学物理研究所,大连116023

出　　处：《膜科学与技术》2023年第3期44-53,共10页Membrane Science and Technology

基　　金：中国科学院战略性先导科技专项(XDC10020203);中国科学院稳定支持基础研究领域青年团队计划项目(YSBR-017)。

摘　　要：复合膜是气体分离膜的一个重要发展方向,近年来得到广泛应用.聚二甲基硅氧烷(PDMS)作为复合膜中间层能够有效防止孔渗现象,但是PDMS的疏水性不利于选择层溶液的涂覆,因此需要对PDMS进行改性.以Pluronic■ F68、Pluronic■ F127、Tween 20、Tween 604种非离子表面活性剂为原料,采用溶胀-去溶胀的方式对PDMS进行改性,并研究其亲水性和气体分离性能.结果表明,4种表面活性剂中Pluronic■ F127的改性结果最佳;溶胀处理的PAN/PDMS复合膜在不影响本体机械性能和热力学性能的同时改变了表面组成;提高了PDMS中间层的亲水性和气体渗透性.经过溶胀改性的PAN/PDMS-Pluronic■ F127复合膜的N_(2)、O_(2)、CO_(2)渗透速率分别达到419.8、831.9、2879.7 GPU;在保证选择性基本不变的情况下,气体渗透速率提高了约70%;且经溶胀改性后的PAN/PDMS-Pluronic■ F127更有利于后续分离层的涂覆.改性后的PAN/PDMS-Pluronic■ F127/Pebax30R51复合膜相较于PAN/PDMS/Pebax30R51复合膜,CO_(2)/N_(2)选择性大幅提高,由22.77提高至45.09,同时CO_(2)渗透速率可以达到272.5 GPU,显示出良好的渗透分离性能.Composite membranes which are an important development direction of membranes for gas separation,have been widely used in recent years.PDMS can effectively prevent pore penetration when it is used as the gutter layer of composite membranes.However,the hydrophobicity of PDMS is not conducive to the coating of the selective layer solution.Therefore,PDMS is urgently needed to be modified.In this paper,four nonionic surfactants-Pluronic■ F68,Pluronic■ F127,Tween20,and Tween60 were used to improve the hydrophilicity and gas separation performance of PDMS by swelling.As the results show,the PAN/PDMS composition membrane modified by Pluronic■ F127 showed the best performance among the four nonionic surfactants.After swelling treatment,PAN/PDMS-Pluronic■ F127 composition membrane had changed the surface composition and its hydrophilicity was enhanced.Compared with PAN/PDMS,the gas permeation performance of PAN/PDMS-Pluronic■ F127 was greatly improved with little change on the mechanical and thermodynamic properties.The N_(2),O_(2),and CO_(2) permeance of PAN/PDMS-Pluronic■ F127 composite membrane reached 419.8 GPU,831.9 GPU,and 2879.7 GPU,respectively,and compared with PAN/PDMS,there was almost an increment of 70% while the selectivity remained mostly unchanged.Compared with PAN/PDMS,Pebax30R51 was more likely to form a defect-free thin selective layer on PAN/PDMS-Pluronic■ F127.When swelling treatment was conducted,the CO_(2)/N_(2) selectivity was improved from 22.77 of PAN/PDMS/Pebax30R51 to 45.09 of PAN/PDMS-Pluronic■ F127/Pebax30R51 composite membrane which was the intrinsic selectivity of Pebax30R51 for CO_(2)/N_(2) separation.Meanwhile,PAN/PDMS-Pluronic■ F127/Pebax30R51 showed CO_(2) permeance of 272.5 GPU.

关 键 词：复合膜 PDMS 溶胀 非离子表面活性剂 气体分离 

分 类 号：TQ051.893[化学工程]