Copolymerization of styrene by diphenylzinc-additive systems I. Copolymerization of styrene/p-tert-butylstyrene by Ph2Zn–metallocene–MAO systems

Copolymerization of styrene (S) and p-tert-butylstyrene (p-ButS) was carried out at 60°C using diphenylzinc–metallocene–MAO systems. Metallocenes bisindenylzirconium dichloride, bis(n-butylcyclopentadienyl) titanium dichloride and cyclopentadienyltitanium trichloride were tried, the latter giving the largest conversion. Copolymers obtained with this system were analyzed by NMR and showed to be syndiotactic in nature and slightly richer in p-ButS than the initial feed from which they were formed.