Characteristics of Stereoregular cis -1,4-Polyisoprene Obtained under the Conditions of a Large-Tonnage Production Process on Titanium and Lanthanide Catalysts Modified in Turbulent Flows

cis- 1,4-Polyisoprene was prepared under conditions of the industrial production process using small high-performance diffuser–confuser tubular turbulent apparatuses in the stage of formation of titanium, neodymium, and gadolinium Ziegler–Natta catalysts, and characteristics of the synthesized rubber were determined. The catalytic systems can be ranked in the following order with respect to the content of cis- 1,4-units in the synthesized polyisoprene: titanium (96.3%)–neodymium (97.5%)–gadolinium (99%); the polyisoprene obtained on lanthanide catalysts contains no trans- 1,4-units. The mean molecular masses of polyisoprene increase in the same order, whereas the polydispersity coefficient varies insignificantly. Natural rubber compared to synthetic analogs contains virtually no thermally stable compounds, is characterized by higher surface microhardness, and contains about 1% volatiles.