Abstract

RABAGLIATI, FRANCO M.; CARO, CARLOS J.  and  PEREZ, MONICA A.. COPOLYMERIZATION OF STYRENE BY DIPHENYLZINC-ADDITIVE SYSTEMS: PART III. COPOLYMERIZATION OF STYRENE/para- METHYLSTYRENE USING CpTiCl₃-MAO and Ph₂Zn-CpTiCl₃-MAO INITIATOR SYSTEMS. Bol. Soc. Chil. Quím. [online]. 2002, vol.47, n.2, pp.137-144. ISSN 0366-1644.  http://dx.doi.org/10.4067/S0366-16442002000200009.

The copolymerization of styrene with p-methylstyrene has been tested using combined diphenylzinc-additive initiator systems, including diphenylzinc, Ph₂Zn, a metallocene: cyclopentadienyltitanium trichloride, CpTiCl₃, and methylalumoxane, MAO, as well as the binary CpTiCl₃-MAO initiator system. Both combined initiator systems were able to induce S/p-MeS copolymerization and the corresponding homopolymerizations. Conversion to copolymer increases with an increase of p-MeS in the initial feed, while p-MeS homopolymerization led to greater conversion than that of S. From the copolymers obtained using these initiator systems only those produced from S/p-MeS = 95/5 (mol/mol) in the feed showed to be crystalline, with Tm values lower than that of pure s-PS, making them easier to process

Keywords : styrene; polymerization; copolymerization; diphenylzinc; metallocenes; catalysts; stereoregularity; tacticity.