Oxidative polymerization of acrylamide in the presence of L-threonine

Abstract

L-threonine/Ce(IV) salts and L-threonine/KMnO4 initiator systems were used for the polymerization of acrylamide, resulting water-soluble poly(acrylamide) which contains hydroxy amino acid end groups. The dependence of polymerization yields and molecular weights of the polymers on the mole ratio of acrylamide (AA)/L-threonine (Thr), the polymerization time, the temperature and the concentration of sulfuric acid was investigated. The decrease in the mole ratio of acrylamide to L-threonine resulted in a decrease in the molecular weight of poly(acrylamide) which contains L-threonine end groups. The maximum yield has been obtained at the mole ratio of n(AA)/n(Thr) = 250, further decrease in the mole ratio of acrylamide to L-threonine resulted in a decrease in the yield of acrylamide polymer. With an increasing sulfuric acid concentration, the polymerization yield decreases. Ce(IV) and Mn(IV) reduced to Ce(III) and Mn(II), respectively, in the polymerization reaction. The amounts of polymer-bound Ce(III) and Mn(II) were determined. The composition of the polymerization products was investigated.