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The eomposition and polymerization activity of a given catalyst system (TiCI4-Et2AlCl) were determined. The solid particles formed by the reaction of the catalyst components were separated at two given times, which were characteristic of the polymerization kinetics. The polymerization activities of the catalyst precipitates were determined in the presence of Et2AlCl and other cocatalysts. It was established that the measured polymerization activities of the catalyst precipitates are higher in the initial system than in the presence of other cocatalysts. The composition of the liquid phase of the catalyst was studied and it was found to contain certain dissolved Ti compounds, the titanium content of which could be determined after hydrolysis as trivalent Ti. The concentration of this titanium compound depends on the solvent used. The polymerization kinetic studies provided evidence that the maximum polymerization rate, i.e., the process of polymerization as a whole, depends on the kind of the solvent used and thus on the quantity of dissolved titanium compounds in the liquid phase.

1. Complexes of VCl4, VOCl3,TiCl4, and AlCl3 with acrylonitrile (AN) were produced, their properties were studied, and it was shown that the coordination of AN with the central atom is accomplished through the unshared pair of electrons of the nitrogen atom. 2. Acrylonitrile stabilizes catalytic systems based on VCl4 but sharply reduces their activity in the polymerization of ethylene. 3. The introduction of AlCl3 into catalytic systems based on acrylonitrile complexes of VCl4 and diisobutyl aluminum chloride promotes an increase in their activity in the polymerization of ethylene. The indicated effect is evidently due to a recoordination of AN from VCl4 to AlCl3. 4. Acrylonitrile is brought into polymerization and forms copolymers with ethylene.

By using a model of the polymerization process, taking into account the reaction of formation and deactivation of active centers with respect to mono- and bimolecular mechanisms, equations have been obtained which describe the kinetics of the polymerization of α-olefins under nonstationary conditions. The possible effect of the polymerization process on the catalyst reaction has been considered.

A direct method is proposed for determining the concentration of active centers by introducing the stable radical 2, 2, 6, 6-tetramethyl-4-hydroxypiperidine-1-oxyl at the commencement, and during the course of, the polymerization process of tetrafluoroethylene. On the basis of the data obtained, the rate constants of the elementary processes are calculated.

A study of the effect of surface-active substances (SAS) on the long-term strength of polypropylene showed that the reduction in strength of this polymer is well correlated with the swelling of specimens in various SAS. It was found that SAS affect the deformability of polypropylene at room and subzero temperatures.