CATIONIC POLYMERIZATION OF 1,3-PENTADIENE INITIATED BY (CH3)(3)SIOSO2CF3 TICL4 SYSTEM/

The polymerization of 1, 3 - pentadiene initiated by TMSOTf/TiCl4 init iating system is reported. The results showed that, the initiating sys tem has an higher activity than TiCl4 alone. It can increase the molec ular weight and raise reaction rate of polymerization. The polymer yie ld increases with the [TMSOTf]/TiCl4 ratio,and then keeps constantly w hen the [TMSOTf]/[TiCl4] ratio is not less than 0.5, The molecular wei ght reaches a maximum when [TMSOTf]/[TiCl4] = 1. The reaction kinetic and reaction mechanism are studied. In our study, the polymerization o f PD is initiated by the TiCl4 in complexation with HOTf released by h ydrolysis of TMSOTf. The yield and the molecular weight increase with steric hindrance of kentone.