聚芳硫醚氧膦基磺酸质子交换膜的制备与表征

Up to now, aromatic proton exchange membranes (PEMs) are the key research of PEMs. Sulfonated poly(arylene thioether phosphine oxide)s are considered to be a promising matrix for PEMs because their phosphine oxide groups exhibit excellent water retention, adhesive ability with inorganic particles or polymers, and oxidation resistance. However, there are few reports on the PEMs of sulfonated poly(arylene thioether phosphine oxide)s. Hence, sulfonated aromatic PEMs containing phosphine oxide groups would be designed and synthesized in present work. Firstly, triphenylphosphine oxide with three sulfonic acid groups is introduced in the backbone of the polymer by polycondensation to obtain the tri-sulfonated poly(arylene thioether phosphine oxide)s, in which the distribution mode of sulfonic acid groups is beneficial to enhance simultaneously the dimensional stability, oxidation resistance and proton conductivity of the membrane. And then, the performance of above systhesized polymer is further improved by crosslinking, introducing functional group, blending, and oxidation methods, so a series of tri-sulfonated poly(arylene thioether phosphine oxide)s PEMs with better over-all properties and promising application value will be obtained. Additionally, the results of these studies will provide theoretical bases and practical instruction to design high-performance sulfonated aromatic PEMs.

芳香族质子交换膜（PEM）是目前PEM研究的重点。磺化聚芳硫醚氧膦聚合物由于其氧膦基团具有良好的吸水保湿性、与无机粒子或聚合物的粘结性及耐氧化性，被认为是优良的PEM基体材料，但目前关于磺化聚芳硫醚氧膦质子交换膜的研究鲜有报道。因此，本项目拟设计合成含氧膦基团的磺化聚芳硫醚氧膦质子交换膜。首先，采用缩聚法将含三个磺酸基团的三苯基氧膦结构单元引入到聚合物主链得到三磺化聚芳硫醚氧膦聚合物，其磺酸基团分布方式有利于同时提高膜的尺寸稳定性、耐氧化稳定性及电导率。然后，将上述聚合物通过交联、引入功能基团、共混、氧化等方法进一步提高其性能，从而得到综合性能优异并具有潜在应用价值的三磺化聚芳硫醚氧膦质子交换膜系列。本项目的实施将对如何提高磺化芳香族质子交换膜的综合性能提供新的思路和理论指导。

磺化聚芳醚（硫醚）氧膦是一种性能优良的质子交换膜基质材料，但将该类膜推向应用，仍需提高膜的尺寸稳定性、耐氧化稳定性和质子电导率，针对此研究目标，本项目开展了如下工作。首先，将含特定官能团的二氮杂萘酮和具有特殊磺酸基团分布方式的三磺化氧膦引入聚合物主链中，合成了含二氮杂萘酮的三磺化聚芳醚氧膦质子交换膜。磺酸基团与杂萘酮羰基分子间氢键的形成，减小了溶胀率，得到尺寸稳定性好的三磺化聚杂萘酮醚氧膦质子交换膜。另外，将巯基二氮杂萘酮与二磺化氧膦单体共聚，制备了耐氧化、低溶胀的二磺化聚二氮杂萘酮硫醚氧膦质子交换膜。 其次，通过共混制备了磺化聚芳醚氧膦/偏氟乙烯共混质子交换膜，结合各组分的优点,制备了溶胀低、电导率和耐氧化性高的磺化聚芳醚氧膦/偏氟乙烯共混膜。最后，通过缩聚合成三磺化聚芳硫醚氧膦，再以性能优异的含芴基的单磺化聚芳醚氧膦作为交联剂，通过交联提高膜的尺寸稳定性和耐氧化性能，同时保证其较高的质子电导率。