Abstract:

The chloromethylated polysulfone (CMPSF) was prepared under relatively mild reaction conditions by using low toxic and non-carcinogenic materials, while ice-bath was innovatively introduced in the experiment. And the response surface methodology (RSM) was used for optimizing the preparation conditions of CMPSF. The results indicate that the highest degree of chloromethylation of polysulfone could reach up to 1.443 mmol·g^-1 while the optimum conditions for preparation are as follows:ice-bath temperature 3.3℃, trimethylchlorosilane dosage 15.63 ml, reaction temperature 35℃, solvent amount 500 ml, stirring rate 200 r·min^-1, catalyst dosage 1.52 ml, reaction time 40 h. Using the optimized CMPSF, quaternized polysulfone (QAPSF) was synthesized by means of quaternization, and then the polysulfone anion exchange membrane (PSFAEM) was carried out finally. The chemical structure of each product was characterized by FT-IR, ¹H NMR and XPS. The main membrane performances were also examined. The results reveals that the membrane surface resistance is 1.05 Ω·cm² and the ion exchange capacity is 1.2 mmol·g^-1. The water uptake and swelling degree of the PSFAEM are 0.42 g·g^-1 and 25.47% respectively. TGA tests also show that quaternary ammonium groups of PSFAEM won't be shed until the temperature reached 140℃. As shown in this research, the acquired PSFAEM can meet the requirements of practical application.

Key words: polysulfone, chloromethylation, response surface methodology, optimization, quaternization, synthesis, membranes

摘要：

选择低毒、无致癌毒性的材料，创新性地使用冰浴手段，在相对温和的反应条件下制备出氯甲基化聚砜（CMPSF），并采用响应面法优化了CMPSF的制备条件。结果表明，当冰浴温度3.3℃、三甲基氯硅烷用量15.63 ml、反应温度35℃、溶剂量500 ml、搅拌速度200 r·min^-1、催化剂用量1.52 ml、反应时间40 h时，CMPSF的氯甲基化程度可达最大值1.443 mmol·g^-1。进一步将优化后的CMPSF原料季铵化，最终制得聚砜阴离子交换膜（PSFAEM（。利用FT-IR、¹H NMR和XPS对各产物的化学结构进行了表征，并测定了阴离子交换膜的主要性能，结果表明所制阴膜的离子交换容量为1.2 mmol·g^-1、面电阻为1.05 Ω·cm²、含水量为0.42 g·g^-1、溶胀率为25.47%，由热重分析结果可知季铵基团脱落温度为140℃，所制阴膜的性能满足实际应用中对阴离子交换膜的要求。

关键词: 聚砜, 氯甲基化, 响应面法, 优化, 季铵化, 合成, 膜