Copolymerization of ethylene or propylene with α-olefins containing hydroxyl groups with zirconocene/methylaluminoxane catalyst

Abstract

Copolymerization of olefins (ethylene and propylene) and 5-hexen-1-ol pretreated with alkylaluminum was performed using [dimethysilylbis(9-fluorenyl)]zirconium dichloride/methylaluminoxane as the catalyst. The copolymerization required extra addition of alkylaluminum to prevent deactivation of the catalyst when 5-hexen-1-ol was pretreated with trimethylaluminum, whereas the triisobutylaluminum-treated system did not require any addition of alkylaluminum. The molecular weight of the copolymer depended on the kind of alkylaluminum compound (masking reagent, additive, and cocatalyst). 13C NMR analysis proved that poly(ethylene-co-5-hexen-1-ol) containing 50 mol % of 5-hexen-1-ol acted as an alternating copolymer, whereas the poly(propylene-co-5-hexen-1-ol) acted as a random copolymer. The surface property of the copolymers was simply evaluated by means of water drop contact angle measurement. It was found that the copolymers containing large amounts of 5-hexen-1-ol units showed good hydrophilic properties.