Synthesis of ultrahigh-molecular-weight ethylene-1-hexene copolymers with high hexene content via living polymerization with fluorinated bis(phenoxy-imine) titanium(IV).

Abstract

The fluorinated FI-Ti catalyst bis[N-(3-propylsalicylidene)-pentafluoroanilinato] titanium(IV) dichloride (PFI) combined with dried methylaluminoxane (dMAO) is investigated for ethylene/1-hexene copolymerization at 50 °C under atmospheric pressure. The reaction shows good livingness and has a high activity at high [H]/[E] molar ratios up to 14. Ultrahigh molecular weight (>1.4 × 10(6) g mol(-1) ) copolymers with high 1-hexene content (>25 mol%) are prepared. Kinetic parameters of the copolymerization with PFI are determined. The first-order Markov statistics applies and the product of the reactivity ratios r1 r2 is close to 1, giving random unit distributions.