Acrylonitrile(AN) homopolymerization and the copolymerization were examined under various conditions in the presence of anhydrous magnesium chloride (MgCl2).The polymers were obtained with high isotacticity.The effect of solvents

reaction temperature

the molar ratio of MgCl2 and AN on AN homopolymerization and the copolymerization and the tacticity of the polymers were investigated.The optimum reactive conditions to obtain the polymers with high isotacticity are as follows:hexane as the solvent

2

2'-azobisisobutyronitrile (AIBN) as the initiator

the temperature of 60℃ and the molar ratio (MgCl2/AN) of 2 ∶1.The effects of monomer concentration and initiator concentration on the AN homopolymerization

AN/IA(itaconic acid) copolymerization

AN/IA/MA(methylacrylate) copolymerization were investigated.The homopolymers and copolymers with highly triad isotactic content (30.2%～55.9%) have been obtained.The polymers were characterized by 13C-NMR and Fourier transform infrared (FTIR) spectra.At the same time

the thermal properties of the polymers were characterized by differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA).The DSC results show that the exothermic peak temperature of the copolymers increases with the degree of isotacticity

as well as the exothermic peaks of copolymers become wider.The TGA results reveal the copolymer with high isotacticity shows rapid weight loss when the temperature is higher than approximately 300℃

the char-yields and thermal stability of the copolymers are decreased with the increasing of the degree of isotacticity.