Macromolecular Rapid Communications, Vol.22, No.18, 1493-1496, 2001
Homopolymerization and copolymerization of isoprene and styrene with a neodymium catalyst using an alkylmagnesium cocatalyst
The catalyst system Nd(acac)(3) . 2 H2O/Bu2Mg/CHCl3 shows a fairly high activity in both the homo- and copolymerization of isoprene (IP) and styrene (St) in toluene at 60 degreesC. Copolymers obtained from various comonomer feed ratios were characterized by means of NMR spectroscopy and gel-permeation chromatography. The polyisoprene and poly(IP-co-St) obtained predominantly consist of cis-1,4 IP units. Monomer reactivity ratios were evaluated to be r(IP) = 5.4 and r(St) = 0.38 in the copolymerization.