The effects of monomer pressure, texture of amorphous SiO2 carrier used and stoichiometry of surface titanium complexes on the profile of the kinetic curves obtained by polymerization of ethylene with high activity catalyst system TiCl4/SiO2-(C2H5)2AlCl-(C4H9)(1.5)(C8H17)(0.5)Mg were studied. It was found that constant polymerization rate was reached for different times but their values did not depend on pressure and carrier used. The results obtained suggest that surface complexes with mole ratio Cl-/Ti4+=2 generate higher number of active centers and higher polymerization rate. A relationship between kinetic studies and productivity, microstructure of polymers synthesized and their physico-mechanical properties is shown.