Synthesis and Characterization of Superabsorbent Polymers from Various Cotton Products

Synthesis of superabsorbent polymers was investigated with the reaction of five kinds of cotton products (new jeans, worn-out jeans, worn-out underwear, a worn-out towel, and worn-out bedding) and succinic anhydride in the presence of 4-dimethylaminopyridine as an esterification catalyst in a mixture of lithium chloride and N-methyl-2-pyrrolidinone, followed by NaOH neutralization. The molecular weight of cellulose composing cotton products was estimated by solution viscometry. The superabsorbent polymer from new jeans showed the highest absorbency in both pure water and NaC1 aqueous solution, while that from worn-out jeans exhibited the lowest absorbency. These results corresponded to the molecular weight of cotton cellulose, i.e., the higher the molecular weight, the higher the absorbency. The superabsorbent polymers of the present study biologically degraded almost completely in 20 days, which shows their excellent biodegradability. (Received April 4, 2005; Accepted in revised form July 21, 2005)