POLYMERIZATION OF METHYL-METHACRYLATE WITH V(ACAC)(3) AND VOCL3 IN COMBINATION WITH METHYLALUMINOXANE

The polymerization of methyl methacrylate (MMA) with V(acac)(3) and VOCl3 in combination with methylaluminoxane (MAO) was investigated. The obtained polymers have a relatively narrow molecular weight distribution ((M) over bar(w)/(M) over bar(n) < 1,5). It was found that the isotactic triad content of the polymers increases with increasing temperature and MAO/V and MAO/MMA mole ratios. The interaction between MMA and MAO has an influence on the tacticity of radically (initiator AIBN) obained polymers: in presence of MAO the fraction of isotactic triads (mm) is higher. The catalytic activity of MAO-containing catalysts (V(acac)(3)/MAO and VOCl3/MAO) was compared with that of AlEt(3)-containing catalysts (V(acac)(3)/AlEt(3) and VOCl3/AlEt(3)). It was not much different, but for MAO as cocatalyst the isotacticity of the resulting PMMA's was higher, and the polydispersity lower, than with AlEt(3) as cocatalyst.