Ultrasonic Irradiation Synthesis and Properties of Copolymers of N,N-Dimethylaminoethylmethacrylate with Chitosan

The copolymerization of N,N-dimethylaminoethyl methacrylate (DMAEMA) on chitosan (CTS) using ultrasonic irradiation was performed in the presence of ammonium persulfate (PSA) at a temperature of 343 K. The effect of the DMAEMA concentration in the reaction mixture on the copolymer yield, the degree and effectiveness of grafting, as well as on the physical–mechanical properties of films obtained on the basis of synthesized copolymers was studied. Copolymers formation was proven by extraction, FTIR spectroscopy, XRD analysis. CTS-graft-poly(DMAEMA) copolymers of various compositions were obtained. The DMAEMA grafting degree reached ~ 145 wt% and its grafting effectiveness was ~ 65 wt% with the ratio [DMAEMA]/[CTS] = 5 mol/(base-mol). The tensile strength (from 15.3 to 37.7 MPa) and deformation (from 68 to 612%) can be varied within a wide range by changing the composition of the copolymer and molecular weight of the grafted poly(DMAEMA) chains. Temperatures of physical transitions of the CTS-graft-poly(DMAEMA) copolymers were determined by the DSC and DMA methods; the resulting films are gas-permeable.