聚丙烯酸基polyHIPEs的辐射和氧化还原引发聚合制备及其吸附性能研究  

Preparation and adsorption property of poly(acrylic acid)-based polyHIPEs through polymerization of O/W HIPE induced byγ-ray radiation and REDOX system

作　　者：宋元瑞 刘华蓉[1] 崔晓玲 邰晨 陈维健 吕志俊 SONG Yuanrui;LIU Huarong;CUI Xiaoling;TAI Chen;CHEN Weijian;LYU Zhijun(Department of Polymer Science and Engineering, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China)

机构地区：[1]中国科学技术大学化学与材料学院高分子科学与工程系,安徽合肥230026

出　　处：《中国科学技术大学学报》2020年第8期1116-1123,共8页JUSTC

基　　金：国家自然科学基金(51373160)资助.

摘　　要：利用γ射线辐射和氧化还原体系分别引发正相高内相乳液(oil-in-water high internal phase emulsions,O/W HIPE)聚合,制备了一种多孔的聚丙烯酸基(polymerized high internal phase emulsions,polyHIPEs).与用作水凝胶的普通干胶材料相比,该法制备出的polyHIPEs具有较高的孔隙率与较为规整的孔结构,而且通过调节HIPE的内相体积,可以获得具有不同孔隙大小的polyHIPEs材料.通过扫描电镜(scanning electronic microscope,SEM)观察,发现γ射线辐射聚合得到的polyHIPEs比氧化还原引发体系得到的具有更有序、更完整的多孔结构.对亚甲基蓝(methylene blue,MB)的吸附测试结果表明,相比化学法制备的样品,辐射法得到的polyHIPEs材料具有更快的吸附速率和更高的饱和吸附量,在250 mg/L亚甲基蓝溶液中,辐射聚合48 h(吸收剂量为151.2 kGy)的样品R-25-48每克可吸附高达1175.9 mg的亚甲基蓝;而辐射聚合8 h(吸收剂量为25.2 kGy)的样品R-25-8的饱和吸水率则高达近120倍.这意味着γ射线辐射聚合过程影响着材料的结构和性能.利用吸附等温线及动力学模型对γ射线辐射聚合制得的polyHIPEs材料的吸附实验结果进行拟合,发现吸附等温线拟合结果较为符合Langmuir模型,动力学拟合结果更符合拟二级动力学模型,这表明吸附机理为单分子层吸附,而吸附过程以化学吸附为主.Porous poly(acrylic acid)-based polyHIPEs were prepared by the polymerization of oil-in-water high internal phase emulsions(O/W HIPEs)initiated byγ-ray radiation and redox system,respectively.Compared with normal dried gel materials used as hydrogels,polyHIPEs prepared from O/W HIPEs have higher porosity and a more uniform pore structure,and their pore sizes can be adjusted by changing internal phase volume.Observed by scanning electron microscope(SEM),polyHIPEs obtained byγ-ray radiation polymerization were found to have a more ordered and completly porous structure than those obtained by redox initiation system.The adsorption tests of methylene blue(MB)on different samples showed that compared with those prepared by chemical method,polyHIPEs obtained by radiation method had a faster adsorption rate and a higher saturation adsorption capacity.The sample R-25-48 ofγ-ray radiation polymerization for 48 h with an absorption dose of 151.2 kGy could adsorb up to 1175.9 mg of methylene blue per gram in 250 mg/L methylene blue solution,and the sample R-25-8 of radiation polymerization for 8 h with an absorbed dose of 25.2 kGy could absorb a lot of water,up to nearly 120 times its original weight,which means that theγ-ray radiation polymerization process affects the structure and properties of polyHIPE materials.The adsorption isotherms and kinetics models were used to fit the adsorption experimental results of MB on polyHIPEs obtained byγ-ray radiation polymerization.It is found that adsorption isotherm fits the Langmuir model and adsorption kinetics conforms to pseudo-second-order model,which indicates that the adsorption process is dominated by chemisorption with the mechanism of monolayer adsorption.

关 键 词：多孔材料 正相高内相乳液 丙烯酸 辐射聚合 亚甲基蓝的吸附 

分 类 号：O644[理学—物理化学]