A study on synthesis and properties of SAPs based on carboxymethyl cellulose

Carboxymethyl cellulose-graft-poly(acrylic acidSodium acrylate-acrylamide) SAPs have been prepared by the free-radical grafting solution polymerization of acrylic acid (AA) and acrylamide monomers (AM) onto carboxymethyl cellulose (CMC) in the presence of N,N′-methylenebisacrylamide as a crosslinker (MBA) and ammonium persulfate (APS) as an initiator. Various factors influencing the water absorbency of the polymer were studied. These include the weight ratio of APS, MBA, and CMC compared to the monomers. The optimal conditions were found as follows: 1% APS, 0.25% MBA, and 10% CMC (weight ratio to monomers). The maximum absorbencies for distilled water and 0.9 wt.% NaCl solution were 406 g/g and 69 g/g, respectively. The structure of the synthesized polymer was confirmed by Fourier Transform Infrared spectroscopy (FTIR). Additionally, the water absorption and water retention behavior of the polymer in soil were investigated. The results showed that this polymer could be employed as a suitable moisture-holding additive in soil for cultivation purposes.