Authors: Fang Zhang Hao Ren Guolin Tong Yulin Deng
Publish Date: 2016/08/24
Volume: 23, Issue: 6, Pages: 3665-3676
Abstract
In this article we reported a facile method for synthesizing poly sodium acrylate PAANamodified TEMPOoxidized cellulose nanofibril TOCN aerogel spheres The water absorbent capacity of the spheres could be as high as 1030 g/g which has never been reported before Practically the 1 wt TOCN suspension was simply dropped into an HCl solution to prepare physically crosslinked TOCN hydrogel spheres Afterwards PAANa an anionic monomer was added into TOCN gel spheres by solution replacement and the monomer was polymerized and grafted to the TOCN spheres in the presence of NNmethylenebisacrylamide as a crosslinker through in situ free radical polymerization The physical crosslinking through hydrogen bonding of the spheres was replaced by chemical crosslinking after washing the gel spheres to neutral which resulted in high volume expansion about 27 times v/v of the washed sphere The expansion rate and morphologies of the obtained hybrid gel spheres were strongly dependent on the dosage of the crosslinker and monomer The structure and morphologies of the hybrid spheres were characterized by FTIR TGA and SEM The waterabsorbing behaviors of the hybrid spheres were dependent on the pH concentration of the salt solution and crosslinker content The freezedried aerogel spheres were highly porous approximately 9988 with density as low as 15 mg/cm3 All results indicated that TOCN–PAANa hybrid aerogel spheres could serve as a new type of superabsorbentThese works were supported by the Doctorate Fellowship Foundation of Nanjing Forestry University and National Natural Science Foundation of China 31470593 and we thank The Priority Academic Program Development of Jiangsu Higher Education Institutions PAPD for the financial support
Keywords: