聚乙烯醇/[Nbmd]OH碱性复合阴离子膜的制备及性能

Preparation and Performance of Alkaline Composite Membrane with Polyvinyl Alcohol/[Nbmd]OH

以吗啡啉与溴代十二烷为原料,合成新型[Nbmd]OH碱性双核离子液体,并将[Nbmd]OH引入聚乙烯醇(PVA)的铸膜液中,通过浇铸法制备了掺杂碱性离子液体的复合阴离子膜PVA/[Nbmd]OH。采用热重分析及扫描电镜对所制备的复合阴离子膜的热稳定性及形貌进行表征。同时考察了离子液体含量对PVA/[Nbmd]OH复合膜的含水率、溶胀性能、力学性能及电导率的影响。结果表明,离子液体含量的增加可提高PVA/[Nbmd]OH复合膜的含水率、溶胀度、电导率等。其中,当碱性离子液体质量分数为20%时,复合膜的综合性能达到最优,此时,膜的含水率和拉伸强度分别达到161.6%和23 MPa,在70℃时,膜的电导率为2.11×10^(-3)S/cm,表明碱性离子液体的引入,能明显改善膜的导电性能,但是拉伸强度受到了一定的影响。

A new [Nbmd]OH basic dicationic morpholine ionic liquid （IL） was synthesized with morpholine and bromododecane. The alkaline composite membrane with [Nbmd]OH and polyvinyl alcohol （PVA） as materials was prepared by solution casting method. The membranes were characterized by thermo gravity analysis （TGA） and scanning electron microscope （SEM）. The water uptake, swelling ratio and electrical conductivity of the membrane were investigated with different content of [ Nbmd] OH ionic liquid. The results reveal that the water uptake and electrical conductivity increase with increase of the IL content. The water uptake and tensile strength are 455.8 % and 23 MPa, respectively. And the optimum electrical conductivity 2.11×10^-3 S/cm is obtained at 70 ℃, with the content of IL 20%. Therefore, the conductivity of the membrane is improved, but the tensile strength decreases by introduce of the Gemini alkaline ionic liquid.