基于低共熔溶剂前端聚合制备大孔水凝胶及其溶胀和吸附性能

Preparation of Macroporous Hydrogel by Frontal Polymerization of Deep Eutectic Solvent and Its Swelling and Adsorption Performance

以丙烯酸(AAc)、丙烯酰胺(AM)为氢键供体(HBD),氯化胆碱(ChCl)为氢键受体(HBA),按一定比例加热合成可聚合低共熔溶剂(DES),进而以DES为反应性绿色溶剂,将DES通过前端聚合(FP)制备大孔聚(丙烯酸-co-丙烯酰胺)(P(AAc-co-AM))水凝胶。采用红外光谱和扫描电镜对水凝胶的结构进行表征,并研究了大孔水凝胶的溶胀动力学、pH敏感性以及对亚甲基蓝(MB)的吸附性能。结果表明,DES聚合后经水洗、冷冻干燥可制得大孔水凝胶。制备的水凝胶具有pH敏感性,其水溶胀遵循non-Fickian扩散机制。大孔水凝胶对MB有良好的吸附去除能力,其平衡吸附量随pH值增大而增大,当pH=12时,大孔水凝胶对MB的平衡吸附量为64mg/g,去除率达85.07%。

Using acrylic acid(AAc)and acrylamide(AM)as hydrogen bond donor(HBD),and choline chloride(ChCl)as hydrogen bond acceptor(HBA),polymerizable deep eutectic solvent(DES)was synthesized by heating at a certain proportion.Subsequently,DES was used as reactive green solvent to be carried out frontal polymerization(FP)to prepare poly(acrylic acid-co-acrylamide)(P(AAc-co-AM))macroporous hydrogels.The structure of the hydrogels was characterized by FT-IR and SEM.In addition,the swelling kinetics,pH sensitivity and methylene blue(MB)adsorption of the macroporous hydrogels were studied.The results show that the macroporous structure of the prepared DES hydrogels was caused by washing and freezing dry after polymerization.DES macroporous hydrogels were pH sensitive and the swelling follows the non-Fickian diffusion mechanism.The hydrogels have good adsorption capacities towards MB.As the pH increases,the amount of MB adsorbed by the hydrogels is increased.When pH=12,the equilibrium adsorption capacity of the macroporous hydrogel to MB is 64 mg/g,and the removal rate is 85.07%.