title: Homogeneous synthesis of chitin-based acrylate superabsorbents in NaOH/urea solution.
abstract: A modified freezing-thawing cyclic (FTC) process was applied to dissolve the chitin in NaOH/urea solution. A transparent homogeneous solution was obtained. It was utilized directly for preparing the superabsorbent polymers (SAPs) by grafting copolymerization under static solution conditions without nitrogen protection. The acrylic acid was used conveniently without prior neutralization. The final products existed as hydrogels without excess reagent emissions. The adsorption capacity and yield of SAP that was prepared in the optimum conditions was 2833 g/g and 81.65%, respectively, higher than one-time FTC program prepared with 2527 g/g and 15.44%. Furthermore, it formed a uniform and transparent gel without any residual chitin particles. The regenerated chitin and SAPs were characterized by SEM, FTIR, XRD, and TG. The samples prepared by the new method presented a more amorphous state with good thermal stability, suggesting that this convenient preparation method for a potential industrial application's pathway.
authors.affiliation: Provincial-Level Experimental and Teaching Demonstration Center of Chemical Materials & Engineering, Chizhou University, Anhui Chizhou 247100, People's Republic of China. liutg137@hotmail.com
authors.forename: Tingguo
authors.initials: T
authors.lastname: Liu
authors.forename: Liwu
authors.initials: L
authors.lastname: Qian
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Kunkun
authors.initials: K
authors.lastname: Zhu
authors.forename: Hongbing
authors.initials: H
authors.lastname: Deng
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Yang
authors.forename: Xin
authors.initials: X
authors.lastname: Wang