The Effect of Temperature on the Grafting of Acrylic Acid onto Carboxymethyl Cellulose

Abstract

SummaryThe grafted copolymer CMC‐g‐PAA has been prepared by graft copolymerization reaction using 10% w/w carboxymethyl cellulose (CMC), acrylic acid (AA), 2.5% w/w benzoyl peroxide (BPO) as initiator, 3.75% w/w methylenbisacrylamide (MBA) as crosslinking agent in distilled water at 30, 50, 70, and 90 °C during reaction periods of 30 to 300 min and composited with 10% w/w montmorillonite for 5 h.The grafted copolymer CMC‐g‐PAA and homopolymer were dried in the oven at 40 °C, then washed with distilled water and aceton. After that the hydrogel material was dried, and subjected to Soxhlet extraction with dioxane to separate the homopolymer, poly(acrylic acid), from the graft copolymer, CMC‐g‐PAA. The water absorption capacities and grafting values of grafted CMC were also determined. The graft copolymer CMC‐g‐PAA obtained at 30 °C has high conversion rate of AA (87.6%). The maximum grafting yield (99.181%) and the lowest of homopolymer formation (0.819%) were obtained at 50 °C. It was observed that polyacrylic acid‐grafted CMC produced at 90 °C had the highest water retention capacity (55.03%). The graft copolymer was characterized by infra‐red spectroscopy to determine the structure of the graft chains.