磺化聚醯亞胺/聚乙烯醇半互穿型網狀結構體作為燃料電池之質子交換膜的研發

Abstract

本研旨在合成一系列之磺化聚醯亞胺/聚乙烯醇（SPI/PVAs）共混聚合物及磺化聚醯亞胺/聚乙烯醇半互穿型網狀（SIPN SPI/cPVA20-GAs）之質子交換膜。 其中SPI 的合成是使用高耐水解的1,4,5,8-萘四酸二酐（NTDA）為二酸酐、4,4’-二氨基二苯醚（ODA）為非磺化二胺單體與具有雙磺酸基之4,4-二（4-胺苯甲基）二苯（BAPBD）單體進行熱醯亞胺化；PVA 分別以5 phr、10 phr與20 phr 的比例混摻於SPI 中而製備出不同組成比例的共混聚合物；將SPI/PVA20 膜浸於30 ℃ 的1 vol% 的戊二醛（GA）水溶液（pH~1.4）中，使GA 對PVA 進行交聯反應，製備出不同交聯程度的半互穿型網狀結構；利用FTIR-ATR 鑑定SPI 的醯亞胺化以及PVA 和GA 的交聯反應特性。 最後利用熱性質分析、含水率、尺寸穩定性、氧化穩定性、質子傳導度、甲醇穿透度以及直接甲醇燃料電池（DMFC）發電效能來分析SPI/PVAs 共混聚合物和SIPN SPI/cPVA20-GAs 的質子交換膜特性。

In this study, a series of polyimide/poly(vinyl alcohol) (SPI/PVAs) polymer blend and semi-interpenetrating networks of sulfonated polyimide/poly(vinyl alcohol) polymer (SIPN SPI/cPVA20-GAs) proton exchange membranes were successfully synthesis. The linear polymer composes of sulfonated polyimide (SPI) derived from 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), sulfonated 4,4'-Bis(4-aminophenoxy)biphenyl (BDSA) and 4,4’-oxydianiline (ODA) were prepared by a thermal imidization reaction. SPI was blended with 5 phr, 10 phr and 20 phr PVA respectively to obtain SPI/PVAs polymer blend membranes. The networks structure of PVA was prepared by immersing SPI/PVA20 membrane in pH~1.4, 1vol% glutaraldehyde (GA) solution at 30℃. By controlling crosslinking time, different crosslinking degree of SIPN SPI/cPVA20-GAs membranes can be obtained. Fourier transform infrared spectroscopy (FTIR-ATR) were utilized to verify the synchronization of the imidization of sulfonated poly(amic acid) (SPAA) and the crosslinking reactions between PVA and GA. The structure-property relationship of proton exchange membranes are discussed in details according to the chemical structure of the various content and crosslinking degree of PVA in the SPI/PVAs polymer blend and SIPN SPI/cPVA20-GAs proton exchange membranes from the viewpoints of thermal stability, water uptake, dimension stability, proton conductivity, oxidation stability, methanol permeability, and direct methanol fuel cell (DMFC) performance.