Solution polymerization and thermal properties of acrylonitrile(AN)-acrylamide(AM) copolymer

Copolymerization of AN and AM with azobisisobutyronitrile (AIBN) as the initiator and AM varying from 0 to 3.78?mol% was carried out in dimethylsulfoxide (DMSO) solution at 60?℃ under nitrogen flow, and copolymers were characterized by elemental analysis (EA), gel permeation chromatography (GPC), Xray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and 13CNMR. Results indicated that the amount of AM had a strong influence on the molecular weight, the polymerization conversion, the composition, the crystalline properties, the stereoregularity, and the thermal properties of the copolymers. The tacticity, the crystallinity and the crystallite size increased with the amount of AM. The presence of AM induced an ionic cyclization mechanism to the copolymers in the stabilization process and the cyclization reaction mechanism gradually changed from free radical to ionic with the increased amount of AM.