具有微相分离结构的UV交联型磺化聚芳醚质子交换膜的制备与性能研究

The performance of current sulfonated poly(arylene ether)s, developed as alternative proton exchange membrane (PEM) materials to replace commercially available Nafion membranes by many researchers, does not meet the requirements for an advanced PEM for fuel cell. This project will design and synthesize novel UV-crosslinkable poly(arylene ether) block copolymers, containing photosensitive chalcone groups in hydrophobic blocks and pedant aliphatic sulfonic acid or sulfonated polystyrene in hydrophilic blocks, as PEM materials for fuel cell application. The sulfonation degree and photosensitivity of the proposed block copolymers will be precisely controlled by polymerization conditions. The morphology and microstructure of the resulting PEMs and the corresponding fuel cell performance will be measured and the effects of chemical structure, membrane forming technique, photocrosslinking method, and crosslinking degree on the properties of PEMs will be investigated. The microphase-seperated PEMs prepared by solution cast or electrospinning technique will be irradiated by UV light in a swollen state to form a percolated crosslinked network in hydrophobic blocks, which will increase proton conductivity and improve methanol permeability of poly(arylene ether) PEMs. The photocrosslinking strategy will also improve mechanical properties, dimensional and oxidative stability, and water uptake property of the resulting PEMs, therefore increases the operating lifetime of a fuel cell. This research will lead to a detailed theoretical understanding of synthesis-structure-property relationship of photosensitive PEMs with high performance, which is of significant theoretical and practical value for the development and application of fuel cell technology.

目前以替代Nafion膜而开发的常见磺化聚芳醚质子交换膜，难以满足质子交换膜的使用要求。本项目拟设计合成在疏水段带有查尔酮结构和亲水段引入脂肪侧磺酸基或聚苯乙烯磺酸基的UV光交联型多嵌段光敏性磺化聚芳醚质子交换膜材料，并通过控制聚合条件准确调控其磺化度和光敏性；通过对质子交换膜的微观形态和性能以及电池性能进行表征和测试，研究聚合物的结构、膜制备方法、光交联方式以及交联程度等对其性能的影响；利用溶液浇铸和静电纺丝方法技术，制备具体明显微相分离结构的质子交换膜，在常温溶胀下UV照射对其进行光交联，使得疏水段形成网络结构，以期提高质子传导率和氧化水解稳定性，同时还提高机械强度、阻醇性、抗溶胀性以及尺寸稳定性，从而提高使用寿命，为制备综合性能优良的质子交换膜奠定坚实的物质和理论基础，这对燃料电池技术的推广应用具有重要的实用价值和理论意义。