【摘要】：本文設(shè)計(jì)了一種多官能團(tuán)離子交換膜制備方法,通過在單體中引入兩個官能團(tuán)提高單位體積內(nèi)離子交換容量(IEC),從而提高離子傳導(dǎo)率。利用密度泛函數(shù)(DTF)理論計(jì)算反應(yīng)能壘,計(jì)算得到雙季銨化單體中活性位點(diǎn)的反應(yīng)能壘相近,證明分子結(jié)構(gòu)設(shè)計(jì)合理,雙季銨化結(jié)構(gòu)單體制備方法可行。以計(jì)算結(jié)果為依據(jù),以降冰片烯二酸酐(NA)為原料,通過酰胺化反應(yīng)、還原反應(yīng)和季銨化反應(yīng)制備了雙官能團(tuán)降冰片烯衍生物單體,采用開環(huán)易位聚合(ROMP)制備了季銨型聚降冰片烯系列陰離子交換膜。通過核磁氫譜(1HNMR)和紅外光譜(FTIR)對降冰片烯衍生物單體和聚合物(L-x、AEM-x)結(jié)構(gòu)進(jìn)行了表征,對制備的五種類型的離子交換膜進(jìn)行各項(xiàng)性能進(jìn)行了測試,發(fā)現(xiàn)交聯(lián)型膜比線型膜具有更強(qiáng)的機(jī)械強(qiáng)度和更低的吸水溶脹率,這主要是因?yàn)榻宦?lián)單體的引入使聚合物線型結(jié)構(gòu)連接成網(wǎng)狀結(jié)構(gòu),使分子結(jié)構(gòu)更加緊密,隨著交聯(lián)單體引入,拉伸強(qiáng)度從6.19 MPa提高到15.18MPa,溶脹率從29.26%降到12.45%。分析電化學(xué)性能發(fā)現(xiàn),AEM-F膜的氫氧根離子傳導(dǎo)率在25℃為64.79 mS·cm-1,接近同等條件下PEMNafion 117的質(zhì)子傳導(dǎo)率,遠(yuǎn)高于同類型陰離子交換膜(AEMs)氫氧根離子(OH-)的離子傳導(dǎo)率。選取AEM-F膜制備膜電極(MEA)并組裝單電池,電池開路電壓在1.02- 1.06V之間,表現(xiàn)出優(yōu)異的氣體阻隔性,最大功率密度達(dá)到151.36 mW·cm-2。然后結(jié)合催化劑用量、氣體流量和電池溫度下電池的極化曲線和功率密度測試數(shù)據(jù)討論了電池性能的影響因素。為了研究OH-傳導(dǎo)機(jī)理,通過分子動力學(xué)(MD)方法模擬AEMs的使用環(huán)境,計(jì)算離子交換膜內(nèi)分子作用關(guān)系和氫氧根離子的運(yùn)動軌跡,進(jìn)一步分析膜內(nèi)的微相結(jié)構(gòu)和氫氧根離子的傳輸機(jī)理,從而對實(shí)驗(yàn)現(xiàn)象進(jìn)行解釋并對以后實(shí)驗(yàn)起到一定的指導(dǎo)作用。
[Abstract]:In this paper, a preparation method of multifunctional ion-exchange membrane is designed. By introducing two functional groups into the monomer, the ion exchange capacity (IEC),) is increased in unit volume to improve the ionic conductivity. The reaction energy barrier was calculated by using the (DTF) theory of density universal function, and the reaction energy barrier of the active site in the double quaternary ammonium monomer was calculated. It is proved that the molecular structure design is reasonable and the preparation method of the double quaternary ammonium monomer is feasible. Based on the calculation results, difunctional norbornene derivatives were prepared by amidation, reduction and quaternary ammonium reaction from norbornic anhydride (NA). A series of quaternary ammonium polynorbornene anion exchange membranes were prepared by ring-opening translocation polymerization (ROMP). The structures of norbornene derivatives monomer and polymer (L-xAEM-x) were characterized by 1HNMR and (FTIR), and the properties of five kinds of ion-exchange membranes were tested. It is found that the cross-linked membrane has stronger mechanical strength and lower water swelling rate than the linear membrane, which is mainly due to the introduction of the cross-linked monomer to make the polymer linear structure connect to the network structure, and make the molecular structure more compact, with the introduction of the cross-linked monomer. The tensile strength was increased from 6.19 MPa to 15.18 MPA, and the swelling rate decreased from 29.26% to 12.45 MPA. By analyzing the electrochemical properties, it is found that the hydrogen oxygen ion conductivity of AEM-F membrane is close to the proton conductivity of PEMNafion 117 at 25 鈩，

本文編號：2296893