以氯丁酰氯(CBC)为小分子试剂,通过傅-克酰基化反应在双酚A型聚砜主链引入可交换氯,制备了氯乙酰基化聚砜(CBPS),然后以羟乙基磺酸钠(HES)为试剂,与氯甲基通过亲核取代反应制备了一种具备较长柔性侧链的一种侧链脂肪磺酸型磺化聚砜(PS-ES),采用红外光谱和核磁氢谱标表征了它们的化学结构,并采用溶液浇注的方法制备了相应的聚砜阳离子交换膜(PSCEM),探索了PSCEM性能和温度之间的关系。结果表明:随着温度的升高,侧链末端的磺酸基团运动能力增强,导致PSCEM的吸水率(WU)、吸水溶胀性(SW)和质子传导率(PC)增加,由于制备的PS-ES膜材具备很长的柔性侧链,使相应PSCEM的亲水基团远离疏水聚合物主链,吸收的水分子被限制在亲水区域,降低了亲水部分对疏水主链的影响,使PS-ES膜在高磺化度下仍具备一定的尺寸稳定性,其中磺酸键合量为1.50mmol/g的PS-ES-3膜在25℃和85℃的吸水率分别是27.6%和43.6%,但是相应的吸水溶胀性仅为25.5%和55.7%,其中PS-ES-3在85℃的质子传导率达到了0.149S/cm,与商业化Nafion115的性能非常接近,表现出很好的综合性能。
Exchangeable chlorine atom was introduced onto the main chain of bisphenol A type aromatic polymers polysulfone(PS) by Friedel-Crafts acylation reaction with chlorobutyryl chloride as a small molecular reagent,chloroacetylated polysulfone (CBPS) was prepared.On the basis of preparation of CBPS,one kind of aliphatic sulfonic type sulfonated polysulfone (PS-ES) with long flexible side chains was prepared by nucleophilic substitution reaction through the reaction of sodium hydroxyethyl sulfonate with chloromethyl group of polysulfone.The chemical structure of the aliphatic sulfonic type sulfonated polysulfone was fully characterized by FT-IR spectroscopy and 1H-NMR spectroscopy.The corresponding aliphatic sulfonic type sulfonated polysulfone cationic exchange membranes(PSCEM) were obtained by solution casting method.The relationship between the properties of PSCEMs and temperature was explored emphasisly.The results shown that with increasing the temperature,the movement capacity of the sulfonic acid group at the end of the side chain of PS-ES increased,leading to the increase of water uptake(WU),swelling ratio (SW) and proton conductivity (PC) of PSCEM.As the obtained PSCEMs had a very long flexible side chains,the hydrophilic sulfonic acid groups of the PSCEM were far away from the main chain of hydrophobic aromatic polymers.The absorbed water molecules were restricted to the hydrophilic region,reducing the influence of hydrophilic sulfonic acid groups on the hydrophobic main chain of aromatic polymers.It leaded to the PSCEMs kep excellent size stability at high water sorption.The PS-ES-3 PSCEM with the bonding amount of sulfonic acid group of 1.50mmol/g had good comprehensive performance that the water uptake at 25℃ and 85℃ were up to 27.6% and 43.6%,respectively.But the corresponding swelling ratio of PS-ES-3 PSCEM was only 25.5% and 55.7%.The proton conductivity of PS-ES-3 PSCEMs at 85℃ was up to 0.149S/cm which was very close to Nafion115 PEMs at the same condition.
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