臭氧预处理制备PVDF接枝SSS离子交换膜

Preparation of PVDF grafted SSS ion exchange membrane by ozone pretreatment

为了降低离子交换膜的制膜费用,同时为后期微生物燃料电池中的应用提供依据和参考,实验研究了用臭氧预处理过氧化苯甲酰(BPO)引发条件制备聚偏氟乙烯(PVDF)接枝对苯乙烯磺酸钠(SSS)聚合物(PVDF-g-SSS)。傅里叶红外分光光度计(FT-IR)确认了产物的化学组成,用溶剂挥发法制得离子交换膜(PS膜)。通过X射线衍射仪(XRD)和X射线光电子能谱仪(XPS)分析了膜的结晶形态及膜面元素组成,并考察SSS单体用量对膜的离子交换容量、电导率及亲水性等性质的影响。结果表明:接枝反应对PVDF晶型影响较小,PS膜表面有S元素生成;臭氧处理后PVDF易与SSS发生接枝聚合反应,且离子交换容量与SSS单体用量成较好的线性关系,当PVDF/SSS的配比为1∶5,PVDF-g-SSS占铸膜液含量的5%时,PS膜的最高离子交换容量可达2.5 mmol·g^(-1),电导率可达0.046 s·cm^(-1)。

The graft polymerization of sodium styrene sulfonate（ SSS） on polyvinylidene fluoride（ PVDF）was carried out using an ozone pretreatment method with benzoyl peroxide（ BPD） as initiator to reduce preparation costs of the ion exchange membrane,while providing the basis for the application of microbial fuel cells. The chemical composition of PVDF-g-SSS was confirmed by Fourier transform infrared spectrophotometry（ FTIR）,while crystal morphology and membrane elements were analyzed by X-ray diffraction（ XRD） and X-ray photoelectron spectroscopy（ XPS）,respectively. A PS ion exchange membrane was fabricated through the solvent evaporation method. In addition,the effects of SSS concentration on the ion exchange capacity（ IEC） and membrane hydrophilicity were investigated. The crystalline PVDF was not significantly affected by the grafting reaction,and sulfur was observed on the PS membrane surface. Furthermore,the graft polymerization reaction proceeded easily following ozone pretreatment of PVDF,and a good linear relationship was obtained between the IEC and the SSS concentration. Finally,the optimal IEC and electrical conductivity of the PS membrane reached2. 5 mmol·g^（-1）and 0. 046 s · cm^（-1）respectively with a PVDF / SSS ratio of 1 ∶ 5 and when the percentage of PVDF-g-SSS in the casting solution was 5%.