【摘要】 采用磷酸和聚乙烯醇(PVA)在尿素存在下发生单酯化反应,合成了一种新型聚阴离子电解质磷酸单酯PVA(PMPVA)。考察了反应时间、反应温度、磷酸用量、尿素用量对取代度的影响。利用傅立叶变换红外光谱(FT-IR)、扫描电镜(SEM)对PMPVA的结构进行了表征,PMPVA的导电和耐热性随取代度的增大而提高。将PMPVA及PMPVA/季铵化聚阳离子PVA(QAPVA)复合物制备的渗透汽化复合膜,用于乙醇/水体系进行渗透汽化分离。PMPVA对水的分离因子α为637,渗透通量J为3903g/(m2.h);PMPVA/QAPVA复合物膜对水的分离因子α为1890、渗透通量J为520g/(m2.h)。更多还原

【Abstract】 A novel polyanion electrolyte Phosphate monoester PVA(PMPVA) was synthesized by phosphate monoesterified PVA with phosphoric acid in the presence of urea.The factors affecting the reaction were investigated.PMPVA exhibited higher glass transition temperature.The conductivity of PMPVA aqueous solution showed the direct proportion relationship with PMPVA concentration. Further prepared PVA and PMPVA into the dense membranes and observed the membrane surface morphology by SEM.It is found that the surface of PVA membrane was flat,whereas the surface of PMPVA membrane took on many flake crystal.The chemical structure of PMPVA also was studied by FT-IR.Pervaporation(PV) membranes were prepared from PMPVA applied in the separation of water/ethanol system(containing 95.4wt% ethanol) at 75℃.They showed the permeation flux of 390g/(m2·h) and the separation factor of 637.Further,the composite membranes were made from PMPVA/ QAPVA(quaternized PVA).The permeation flux of 520g/(m2·h) and separation factor of 1890 for water/ethanol system(containing 95.4wt% ethanol).更多还原