Novel Supports for Ethylene Polymerisation Based on Polystyrene Polymers

The industrial use of metallocene/methylaluminoxane catalytic systems and late transition metal catalysts requires the use of supports to directly get polyethylene (PE) with spherical morphology. The presence of residues of the inorganic support gives rise to PE contamination problems, therefore less contaminating organic supports may present an interesting alternative. In this work, linear hydroxypolystyrene (PS-OH) and polystyrene-block-isoprene copolymer (PS-b-PI) were tested as supports for ethylene polymerisation. The ability of these polymers when dissolved in a selective solvent to form micelles or aggregates, was investigated by light scattering techniques. Next, their capacity to act as MAO or TMA-activated supports towards MeDIP(2,6-iPrPh₂FeCl₂) catalyst was analysed by carrying ethylene polymerisation tests and PE morphology studies. The PS-b-PI copolymer, used as organic support in heptane, enabled the obtention of PE with well defined spherical morphology.