Development of titanium based post metallocene catalytic systems for aqueous emulsion polymerization

Abstract

Increasing need of polyolefins in majority of industrial domains is due to wide number of applications such as electrical insulator coating packaging petroleum additives and many more Therefore a number of new metallocene and post metallocene metal based catalysts were synthesized to fulfill the need of industrial production process of polyolefins An extensive work has been reported on cyclopentadiene based metal catalysts therefore the study of post metallocene based catalyst systems have attracted intensive attention as they are reported to produce a variety of stereocontrolled polyolefins Especially group 4 metal complexes were reported to be highly effective and instrumental for the study of the polymerization mechanism interrelationship between physical properties and polymer structure and the synthesis of tailored microstructure along with stereoregularity Therefore promising advancement has been made in the development of single site polymerization catalysts supported by various type of multidentate ligand frame work of all the new highly active post metallocene metal complexes complexes bearing phenoxy imine backbones are one of the promising metal complexes Extensive study in this field is an ever growing area therefore number of new ideas for catalyst design came into limelight Side arm approach is one of the successful strategy for the synthesis of highly efficient post metallocene metal precursors Electronically active ligand systems were reported to bear N O and P as a common donor. newline newlineFurther study on extra donor group suggested that the catalyst bearing soft donor groups like sulphur is found to be highly active and efficient for catalyzing olefins polymerization. All these post-metallocene metal complexes were reported to catalyze polymerization reactions in organic solvents in presence of MAO as a counter anion. Methylaluminoxane is found to be hazardous and reported to poison the ligand backbone