Study of immobilized catalysts. XXI. Synthesis and structure of titanomagnesium catalysts on polymer carriers

Methods of synthesis of polymer carriers with an organometallic functional coating were developed, and grafted titanomagnesium catalysts (GTMC) based on them were obtained. The formation of isolated Ti(III) ions was detected by the EPR method. Depending on the conditions of synthesis and type of polymer carrier, their amount reached 55% of the immobilized titanium. Experimental proofs were obtained for the formation of Ti(III) via the stage of alkylation of Ti(IV) by a magnesium-containing coating. Based on the dependence of the g-factor of the Ti(III) signals on the conditions of its formation, it was suggested that the fragments of the polymer carrier enter the coordination sphere of Ti(III) at low Ti(III) concentrations in the GTMC and that stratification reactions of Ti(III) take place at high concentrations. The existence of crystallites of the active phase with dimensions of the regions of coherent scattering of 40-75 A was found by x-ray diffraction analysis. A correlation was found between the activity of GTMC in the polymerization of ethylene and the Ti(III) content in them in the form of isolated ions.