Organophosphorus complexones as catalysts for but-1-ene polymerization

The isotacticity of the polymer prepared by olefin polymerization catalyzed by the TiCl4/MgCl2/AlEt3 system depends significantly on the type of chelating complexones added to the catalyst (external donor D), the most common of which are dialkyldialkoxysilanes [1, 2]. However, the search for other type D compounds providing the required set of catalyst properties is being continued. Specifically, this problem is actual for the synthesis of isotactic polybut-1ene (PB) which is of great practical importance [2]. Studying but-1-ene polymerization we found that the TiCl4/MgCl2/AlEt3/diisobutyl phthalate catalyst (internal donor) can be modified with polydentate phosphine oxides as external donors D. Such phosphine oxides were previously proposed as solvating agents and polar solvents [3, 4].