MWCNT/poly(MMA-AM)杂化膜的原位聚合制备及其苯与环己烷的吸附-溶胀性能

Preparation and sorption-swelling performance of MWCNT/poly(MMA-AM) hybrid membranes

多壁碳纳米管(MWCNT)经HNO3/H2SO4混酸氧化处理、二氨基-二苯甲烷化学修饰后,得到胺功能化多壁碳纳米管(MWCNT—NH2);通过原位聚合制备多壁碳纳米管/甲基丙烯酸甲酯-丙烯酰胺共聚物杂化膜。采用拉曼光谱、红外光谱、扫描电镜表征了多壁碳纳米管化学修饰前、后的结构和形貌;采用扫描电镜和zeta电位仪分析了杂化膜的结构和表面荷电特性;实验考察了杂化膜在苯、环已烷中吸附-溶胀性能。研究结果显示,MWCNT—NH2/poly(MMA-AM)杂化膜的表面zeta电位随MWCNT—NH2填充量的增加而增大,MWCNT—NH2在杂化膜中分散性较好;在碳纳米管填充量相同的情况下,MWCNT—NH2/poly(MMA-AM)杂化膜的苯平衡吸附-溶胀度与苯/环己烷吸附-溶胀选择性大于MWCNT/poly(MMA-AM)杂化膜。MWCNT—NH2/poly(MMA-AM)杂化膜的苯平衡吸附-溶胀度与苯/环己烷平衡吸附-溶胀选择性随MWCNT—NH2填充量的增加而增大;而MWCNT/poly(MMA-AM)杂化膜的苯平衡吸附-溶胀度随MWCNT填充量的增加略有增大,苯/环己烷平衡吸附-溶胀选择性随MWCNT填充量的增加呈下降趋势。研究结果表明,MWCNT—NH2/poly(MMA-AM)杂化膜对苯/环己烷具有苯优先选择吸附-溶胀的特性,且苯优先选择吸附-溶胀的特性随杂化膜中MWCNT—NH2填充量的增加而更加显著。

Multi-walled carbon nanotubes（MWCNT） were modified by HNO3/H2SO4 mixture and diaminodiphenyl methane（MWCNT-NH2）, and then MWCNT-NH2/poly（MMA-AM） hybrid membranes were prepared through in-situ copolymerization of MWCNT--NH2, methyl methacrylate（MMA） and acrylamide （AM）. The structure of MWCNT,and MWCNT--NH2 were characterized by Raman spectrum, FT-IR, scanning electron rnicroseopy（SEM）. The structure and performance of the hybrid membranes were analyzed by SEM,zeta potential and sorption-swelling behavior. The results shown that the modification of MWCNT promoted the dispersion of MWCNT--NH2 in MWCNT--NHz/poly（MMA-AM） hybrid membranes. The equilibrium swelling degree of benzene（A∞,b） was higher than that of cyclohexane（A∞. c） in the hybrid membranes, but the sorption-swelling selectivity of benzene to cyclohexane（as.b/c） of MWCNT--NHe/poly（MMA-AM） was higher than that of MWCNT/poly（MMA-AM）. A∞,b and as,b/c increased with increase of MWCNT NH2 content（c） in MWCNT--NH2/poly（MMA-AM） hybrid membranes, and the equilibrium swelling degree of cyclohexane （A ） was less changed. MWCNT--NH2/poly（MMA-AM） hybrid membrane displays a characteristics of benzene preferentially selective sorption-swelling for separation of benzene/cyelohexane mixture.