Abstract
In this work, by potentiometric titration the dissociation of the grafted chains of polyacrylic acid in copolymer composition have been investigated. An increase in the content of units of AA in the copolymer leads to a decrease in the values of dissociation constants, that is, the acidic properties are weaken. It was shown that with the extension of the grafted copolymer chains in MC-g-PAA, as well as the enhance the interaction between the basic and graft chains of the copolymer intra- and intermolecular complexes are formed by hydrogen bonding system. Also, by viscometry the effect of the temperature and pH on the rheological properties as well as phase transitions in aqueous solutions of graft copolymers based on polyacrylic acid and methyl cellulose (MC-g-PAA) have been investigated. It was demonstrated that the content of the grafted polyacrylic acid affects to the physicochemical characteristics of the grafted copolymer. Grafting of AA onto a polysaccharide chain allows to create pH-dependent system, resulting in an increase in the solution viscosity of the copolymer with increasing pH.