Synthesis and properties of superabsorbent carboxymethyl cellulose graft-poly(acrylic acid-co-acrylamide)

Abstract

A NEW cellulose-based superabsorbent polymer, carboxymethyl cellulose-graft-poly(acrylic acid-co-acrylamide), was prepared by the free-radical grafting solution polymerization of acrylic acid (AA) and acrylamide (AM) monomers onto carboxymethyl cellulose (CMC) in the presence of N,N'-methylenebisacrylamide (NMBA) as a crosslinker with a redox couple of sodium perborate, thiourea as an initiator. The influences of reaction variables such as crosslinker content, bath temperature, molar ratio of AA to AM, and weight ratio of the monomers to CMC on the water absorbency of the carboxymethylcellulose-graft-poly(acrylic acidco-acrylamide) copolymer were investigated. The copolymer's structures were characterized with Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscope (SEM), Differential scanning calorimetry (DSC) , Thermogravimetric Analysis (TGA).