| Anion exchange membrane（AEM）is an important component of anion exchange membrane fuel cell（AEMFCs）,which directly determines the performance of fuel cell.At present,AEM still has the problems of low alkaline stability and difficult balance between ionic conductivity and dimensional stability.In view of the above problems,this paper prepared three kinds of cross-linked AEM from the perspective of polymer side chain,cationic group design and cross-linking mode,and discussed the influence of polymer and functional cation structure,cross-linking mode and cross-linking degree on the performance of AEM.（1）UV cross-linked ion cluster type quaternary ammonium poly（aryl ether sulfone）anion exchange membrane with was prepared.Firstly,a 200%chloromethylation polyaryl ether sulfone（PSF200）was synthesized,then 70%chalcone was added as crosslinking structure,and the side-chain photosensitive chloromethylation polyaryl ether sulfone（PSPSF-CM70）was synthesized by Williamson etherification and chlorination.And using UV cross-linked ion cluster type quaternary ammonium poly（aryl ether sulfone）anion exchange membrane（QPSPSF70-bis QA130）was prepared by uing 1-（N,N-dimethylamine）-6-（N’,N’,N’-dimethylhexyl）hexane bromide（N6C6N6Br）.Its structure was characterized by 1H-NMR,UV-Vis and FT-IR.QPSPSF70-bis QA130 has good photosensitivity.-CH=CH-on chalcone structure will take place[2+2]cycloaddition reaction to form cyclobutane structure under UV light,so polymer molecules can be crosslinked with the maximum photocrosslinked degree of 66.9%.AEM with different crosslinking degree was prepared by UV light irradiation for different time at room temperature.AEM before and after cross-linking had good film formation,and obvious microphase separation structure could be observed in the AFM phase diagram.The IEC value of the uncrosslinked membrane is 1.73 mmol g-1,and the WU,SR andσare 229.1%,53.5%and 168.0 m S/cm respectively at 80℃.Compared with the uncrosslinked membrane,the WU and SR rates of the crosslinked membrane are 41.3%and 35.95%lower,respectively.The maximum IEC value andσdecreased by 6.9%and 16.9%respectively.After soaking in 1 mol/L Na OH at 60℃for 7 days,theσof the uncrosslinked membrane remains only 78.6%of the initial value,while theσof the crosslinked membrane remains 91.9%.Compared with uncrosslinked films,the tensile strength and initial decomposition temperature of crosslinked films are increased by 19.01MPa and4℃,respectively.Cross-linking can effectively improve the dimensional stability,alkaline stability,thermal stability and mechanical properties of AEM.（2）UV cross-linked ion cluster type piperidine functionalized poly（aryl ether sulfone）anion exchange membrane were prepared.UV cross-linked ion cluster type piperidine functionalized poly（aryl ether sulfone）anion exchange membrane（QPSPSF70-bis Pip130）was prepared by using 1-（N-methyl-4-piperidine）-3-（N’,N’-dimethyl-4-piperidine）propane iodide reacting with PSPSF-CM70.The structure of the membrane was characterized by 1H-NMR,UV-Vis and FT-IR.QPSPSF70-bis Pip130also has good photosensitivity,and the maximum photocrosslinking degree is 56.6%.AEM with different crosslinking degree is prepared by UV light irradiation for different time under normal temperature swelling state.AEM before and after cross-linking had good film formation,and obvious microphase separation structure could be observed in the AFM phase diagram.It’s IEC value is similar to that of quaternary ammonium AEM.At 80℃,WU and SR are 79.6～280.9%and 73.8-74.6%smaller than that of quaternary ammonium AEM,whileσis only 16.4-21.3%smaller than that of quaternary ammonium AEM.After soaking in 1mo L/L Na OH at 60℃for 7 days,the maximumσof piperidinium type AEM can maintain 95.7%of the initial value,while that of quaternary ammonium type AEM can only maintain 91.9%.The tensile strength and elongation at break of PIperidinium type AEM are 7.69～215.02 MPa and 2.2～28.1%,respectively,and there is a big difference between uniform quaternary ammonium type AEM.The initial decomposition temperature of piperidine AEM is 250～253℃,which is about 30℃higher than that of quaternary ammonium AEM.Compared with quaternary ammonium AEM,piperidinium AEM possesses better dimensional stability,alkaline stability and thermal properties,although its ionic conductivity is slightly lower.（3）Thermally cross-linked ion cluster type quaternary ammonium poly（aryl ether sulfone）anion exchange membrane with was prepared.First,chloromethylated polyaryl ether sulfone（PSFx）with chloromethylated rates of 150%and 200%was synthesized.Then,side-chain chloromethylated polyaryl ether sulfone（PSF-CMX）was synthesized by Williamson etherification and chlorination.Then,three thermal crosslinked quaternary ammonium poly（aryl ether sulfone）anion exchange membranes（c QPSF-bis QAx-TAPy）were prepared by controlling the amount of crosslinking agents 2,4,6-tris（dimethylaminomethyl）phenol（TAP）and NCNC6Br.,and the structures of the polymers were characterized by 1H-NMR and FT-IR.c QPSF-bis QAx-TAPy has good film formation and obvious microphase separation structure can be observed in THE AFM phase diagram with gel fraction ranging from 50.8 to68.5%.The IEC value of thermal crosslinked AEM is higher than that of photocrosslinked AEM,reaching 2.07～2.35 mmol g-1,which makes it have higher WU,SR andσ.At 80℃,the WU,SR andσof c QPSF-bis QAx-TAPy are 83.0～192.6%,20.3～58.8%and 112.7～173.7%,respectively.The initial decomposition temperature of c QPSF-bis QAx-TAPy is above 200℃,the tensile strength and elongation at break of c QPSF-bis QAx-TAPy are 9.79～20.11 Mpa and 11.1～20.3%,respectively.After soaking in 60℃1mol/L Na OH for 7 days,theσcan maintain the initial 90.3～93.2%.c QPSF-bis QAx-TAPy showed good ionic conductivity,alkaline stability,mechanical and thermal properties. |
