Characterization and Preparation of Cyclized Cis-1,4 polybutadiene

The soluble cyclizated cis-1,4 polybutadiene with cationic composite catalyst,BzCl/Al(i-Bu)_2Cl and BzCl/AlEt_2Cl) in xylene was obtained without gel by-products.The molecular weight distribution and glass transition temperature of the cyclizated cis-1,4 polybutadiene were characterized by GPC and DSC,repectively.The results show that with the increasing of molar ratio of BzCl/Al(i-Bu)_2Cl and BzCl/AlEt_2Cl),the cyclization degree would increase,and the chain segment of cis-1,4 polybutadiene would become short and thick.As the(Mn) of the cyclizated cis-1,4 polybutadiene would decrease while the D would be broadened,the Tg of cyclizated cis-1,4 polybutadiene would increase correspondingly.