Barrer Centre, Department of Chemical Engineering, Imperial College London , South Kensington, SW7 2AZ London, United Kingdom.
ACS Appl Mater Interfaces. 2017 Nov 8;9(44):38612-38620. doi: 10.1021/acsami.7b13076. Epub 2017 Oct 25.
Semihomogeneous cation exchange membranes with superior ion exchange capacity (IEC) were synthesized via a novel polymerization and sulfonation approach in porous polypropylene support. The IEC of membranes could reach up to 3 mmol/g because of high mass ratio of functional polymer to membrane support. Especially, theoretical IEC threshold value agreed well with experimental threshold value, indicating that IEC could be specifically designed without carrying out extensive experiments. Also, sulfonate groups were distributed both on membrane surface and across the membranes, which corresponded well with high IEC of the synthesized membranes. In addition, the semifinished membrane showed hydrophobic property because of the formation of polystyrene. In contrast, the final membranes demonstrated super hydrophilic property, indicating the adequate sulfonation of polystyrene. Furthermore, when sulfonation reaction time increased, the conductivity of membranes also showed a tendency to increase, revealing the positive relationship between conductivity and IEC. Finally, the final membranes showed sufficient thermal stability for electrodialysis applications such as water desalination.
通过在多孔聚丙烯支撑体上的一种新颖聚合和磺化方法，合成了具有优异离子交换容量（IEC）的半均相阳离子交换膜。由于功能聚合物与膜支撑体的高质量比，膜的 IEC 可高达 3mmol/g。特别是，理论 IEC 阈值与实验阈值吻合较好，表明可以在不进行广泛实验的情况下专门设计 IEC。此外，磺酸盐基团既分布在膜表面，也分布在膜内，这与所合成的膜具有高 IEC 相对应。此外，由于聚苯乙烯的形成，半制成膜表现出疏水性。相比之下，最终的膜表现出超亲水性，表明聚苯乙烯的磺化程度足够高。此外，随着磺化反应时间的增加，膜的电导率也呈现出增加的趋势，这表明电导率与 IEC 之间存在正相关关系。最后，最终的膜表现出足够的热稳定性，适用于电渗析等水脱盐应用。
