Synthesis of novel membranes of polyimide with side-chains and their pervaporation performance

doi:10.3969/j.issn.0438-1157.2013.02.025

Abstract

Abstract: Two novel aromatic diamines 3,5-diaminobenzophenone (PDA) and 4-(trifluoromethyl)phenyl 3,5-diaminobenzoate (FPDA) were mixed separately with 4,4'-diaminodiphenyl ether (ODA) and 3,5-diaminebenzoic acid (DABA) with different ratios, and then copolymerized separately with 4,4'-oxydiphthalic anhydride (ODPA), 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) to give poly(amic acid)s, which were converted into cross-linked polyimides (PIs) with ethylene glycol (EG) by thermal imidization.The structures of these series of PIs were characterized by FT-IR, NMR and GPC.The effect of side-chain content on the thermal stability was investigated by DSC and TGA.The effects of the fluorine group on the properties and separation performance of side-chain polyimides were investigated.The membranes of polyimide obtained were employed in pervaporation separation of benzene/cyclohexane mixtures.The two side-chain polyimide membranes containing 6FDA have an optimal separation efficiency in terms of both flux and separation factor.The cross-linked 6FDA-FPDA/ODA/DABA (1:7:2) membranes show the most promising separation performance with a flux of 9.84 kg·μm·m^-2·h^-1 and separation factor of 6.1 for benzene/cyclohexane (50/50,mass ratio) at 50℃.

Key words: polyimide, side-chains, pervaporation, benzene/cyclohexane

摘要： 针对苯/环己烷混合物体系的特点,采用两种新型侧链二胺3,5-二氨基苯甲酸苯酯(PDA)和3,5-二氨基苯甲酸-4-三氟甲基苯酯(FPDA),制备了一系列由不同二酐与二胺单体如4,4'-二氨基二苯醚(ODA)和3,5-二氨基苯甲酸(DABA)聚合而成的用于渗透汽化分离苯/环己烷的聚酰亚胺膜,对其结构和各项性质进行了表征,并对膜材料的微观结构与宏观分离性能之间的关系进行了较为深入的研究。随着侧链二胺的引入,聚酰亚胺膜的分离效率随之持续增大,分离能力得以改善。渗透汽化实验结果表明,以6FDA为二酐单体的两类聚酰亚胺膜具有较优异的分离性能。乙二醇交联的6FDA-FPDA/ODA/DABA(1:7:2)膜综合渗透汽化分离性能最优。在50℃时,对于含苯50 %(质量)的苯/环己烷混合物,其渗透通量为9.84 kg·μm·m^-2·h^-1,分离因子达6.1。

关键词: 聚酰亚胺, 侧链, 渗透汽化, 苯/环己烷

CLC Number:

QIN Lin, LI Jiding, ZHENG Dongju, WANG Tao. Synthesis of novel membranes of polyimide with side-chains and their pervaporation performance[J]. CIESC Journal, 2013, 64(2): 590-599.

秦琳, 李继定, 郑冬菊, 王涛. 新型侧链型聚酰亚胺膜的制备及其渗透汽化分离性能[J]. 化工学报, 2013, 64(2): 590-599.

References 26

[1]	Shao P, Huang R.Polymeric membrane pervaporation[J].Journal of Membrane Science,2007, 287(2):162-179
[2]	Jonquieres A, Clement R, Lochon P, et al.Industrial state-of-the-art of pervaporation and vapour permeation in the western countries[J].Journal of Membrane Science, 2002, 206(1/2):87-117
[3]	Smitha B, Suhanya D, Sridhar S, et al.Separation of organic-organic mixtures by pervaporation — a review[J].Journal of Membrane Science, 2004, 241(1):1-21
[4]	Villaluenga J, Tabe-Mohammadi A.A review on the separation of benzene/cyclohexane mixtures by pervaporation processes[J].Journal of Membrane Science,2000, 169(2):159-174
[5]	Baudot A, Marin M.Pervaporation of aroma compounds:comparison of membrane performances with vapour-liquid equilibria and engineering aspects of process improvement[J].Food and Bioproducts Processing, 1997, 75(C2):117-142
[6]	Feng X S, Huang R.Liquid separation by membrane pervaporation:a review[J].Industrial & Engineering Chemistry Research, 1997, 36(4):1048-1066
[7]	Jiang L Y, Wang Y, Chung T S, et al.Polyimides membranes for pervaporation and biofuels separation[J].Progress in Polymer Science, 2009, 34(11):1135-1160
[8]	Wilson D,Stenzenberger H D,et al.Polyimides[M].Glasgow and London:Blaekie&Son Ltd., 1990
[9]	Lai H, Qin L, Liu X Y, et al.Synthesis of novel polyimides with (tert-butyldimethylsiloxy)biphenyloxy groups and the effect of side-chains content on their properties[J].European Polymer Journal, 2008, 44(11):3724-3731
[10]	Hillock A, Koros W J.Cross-linkable polyimide membrane for natural gas purification and carbon dioxide plasticization reduction[J].Macromolecules, 2007, 40(3):583-587
[11]	Liaw D J, Wang K L, Huang Y C, et al.Advanced polyimide materials:syntheses, physical properties and applications[J].Progress in Polymer Science, 2012, 37(7):907-974
[12]	Ding M X.Polyimides :Chemistry, Relationship Between Structure and Properties and Materials[M].Beijing:Science Press, 2006:36
[13]	Bettermann I, Staudt C.Desulphurization of kerosene:pervaporation of benzothiophene/N-dodecane mixtures[J].Journal of Membrane Science, 2009, 343(1/2):119-127
[14]	Connell J W, Smith Jr J G, Hergenrother P M.Properties of imide oligomers containing pendent phenylethynyl groups[J].High Performance Polymers, 1997, 9(3):309-321
[15]	Wind J D, Staudt-Bickel C, Paul D R, et al.Solid-state covalent cross-linking of polyimide membranes for carbon dioxide plasticization reduction[J].Macromolecules, 2003, 36(6):1882-1888
[16]	Weng C J, Jhuo Y S, Huang K Y, et al.Mechanically and thermally enhanced intrinsically dopable polyimide membrane with advanced gas separation capabilities[J].Macromolecules, 2011, 44(15):6067-6076
[17]	Gu Y Y, Lodge T P.Synthesis and gas separation performance of triblock copolymer ion gels with a polymerized ionic liquid mid-block[J].Macromolecules, 2011, 44(7):1732-1736
[18]	Zhu J H, Wei S Y, Chen X L, et al.Electrospun polyimide nanocomposite fibers reinforced with core-shell Fe-FeO nanoparticles[J].Journal of Physical Chemistry C, 2010, 114(19):8844-8850
[19]	Wang Z B, Ge Q Q, Shao J, et al.High performance zeolite Lta pervaporation membranes on ceramic hollow fibers by dipcoating-wiping seed deposition[J].Journal of the American Chemical Society,2009, 131(20):6910
[20]	Pithan F, Staudt-Bickel C, Hess S, et al.Polymeric membranes for aromatic/aliphatic separation processes[J].Chemphyschem, 2002, 3(10):856-862
[21]	Ribeiro C P, Freeman B D, Kalika D S, et al.Aromatic polyimide and polybenzoxazole membranes for the fractionation of aromatic/aliphatic hydrocarbons by pervaporation[J].Journal of Membrane Science, 2012, 390:182-193
[22]	Yang L M, Kang Y, Wang Y L, et al.Synthesis of crown ether-containing copolyimides and their pervaporation properties to benzene/cyclohexane mixtures[J].Journal of Membrane Science, 2005, 249(1/2):33-39
[23]	Jiang L Y, Chung T S.Beta-cyclodextrin containing matrimid (R) sub-nanocomposite membranes for pervaporation application[J].Journal of Membrane Science, 2009, 327(1/2):216-225
[24]	Ren J Z, Staudt-Bickel C, Lichtenthaler R N.Separation of aromatics/aliphatics with crosslinked 6Fda-based copolyimides[J].Separation and Purification Technology, 2001, 22/23(1/2/3):31-43
[25]	Ye H, Li J, Lin Y, et al.Synthesis of polyimides containing fluorine and their pervaporation performances to aromatic/aliphatic hydrocarbon mixtures[J].Journal of Macromolecular Science Part A-Pure and Applied Chemistry, 2008, 45(2):172-178
[26]	Qi R B, Wang Y J, Li J D, et al.Pervaporation separation of alkane/thiophene mixtures with Pdms membrane[J].Journal of Membrane Science,2006, 280(1/2):545-552