STEREOSPECIFIC POLYMERIZATION OF PROPYLEN E IN THE PRESENCE OF HIGHLYDISPERSED GRAPHITE AND BORON-NITRIDE

The influence of the method of formation of the catalytic system TiCl4 -(C2H5)2AlCl in the presence of boron nitride and graphite on the kine tic parameters of the propylene polymerization process, and on the pro perties of the forming polymer was studied. It was shown that on the f ormation of the Ziegler-Natta catalytic system in the presence of the supports used, highly reactive stereospecific systems can be obtained for propylene polymerization. The method of preparing catalyst and the type of support influence the nature of the isotactic active centers which are formed on the surface. With the help of I R and NMR C-13 spe ctroscopy and gel-chromatography, several characteristics of the formi ng polypropylene were investigated.