Graft copolymerization of acrylic acid onto hydrolyzed potato starch using various initiators

Abstract

This work presents synthesis and characterization of copolymer obtained by grafting of acrylic acid on hydrolyzed potato starch in the presence of various initiators (azobisisobutyronitrile, potassium persulfate and benzoyl peroxide). Starch hydrolysis was made to reduce average molar mass, i.e. to reduce macromolecule size. Grafting of monomer was performed to produce a product that can be used in textile treatment, for example, in yarn sizing. Various initiators were used, primarily, to produce graft polymer on starch and to obtain thinner or thicker packaging of side chains that can have a great influence on the behavior of textile yarns impregnated with these copolymers. Potassium persulfate, as initiator, proved to be very successful in grafting of acrylic acid on hydrolyzed starch, in terms of yield results, graft percentage and efficiency. FTIR spectra of hydrolyzed and grafted starch confirm by their characteristic bands that grafting was successful. Results show that the highest quantity of monomer is found in the sample of hydrolyzed starch grafted in the presence of benzoyl peroxide. Molar masses of hydrolyzate and copolymer show significant differences ranging from 1.83 × 10³ to 7.13 × 10⁶ g/mol.