Synthesis, molecular characteristics, and stimulus-sensitivity of graft copolymer of chitosan and poly(N,N-diethylacrylamide)

Abstract

Thermo- and pH-sensitive graft copolymer with chitosan backbone and side chains of poly-N,N-diethylacrylamide was synthesized using method of radical graft polymerization. The structural, hydrodynamic, conformational, and thermo-sensitive properties of prepared sample were investigated by light scattering, turbidimetry, and viscometry methods. The grafting density of the side chains of investigated sample is 0.15. Kuhn segment length of obtained copolymer are close to those of the initial chitosan. The behavior of the synthesized copolymer in the buffer solutions is similar to that observed for linear thermo-and pH-sensitive polymers. The phase separation temperature increases with dilution and pH decreasing. A distinctive feature in the behavior of the copolymer obtained is a long duration of the processes of establishing of the equilibrium solution characteristics after a change in temperature.