The possibility of using atactic polypropylene as the main component of thermoplastic elastomers was investigated. It was shown that dynamically vulcanized mixtures of atactic polypropylene and ethylene–propylene–diene rubber have good deformation characteristics, reduced hardness, and low residual elongation.

Изучены реакции полимеризации этилена на комплексах CoCl2 и FeCl2 с N,N,N-тридентатным лигандом, 2,6-бис[1-(2,6-диметилфенилимино)этил]пиридин (L).

The polymerization of ethylene and propylene and the copolymerization of ethylene with 1-octene with novel type of post-metallocene catalysts containing ionic complexes [2L·M@dibenzo-18-crown-6]+ [TiCl5·L]– (L = CH3CN, M = Li, K) are studied. The binary activator Al(C2H5)2Cl/Mg(C4H9)2 at [Al] : [Mg] 3 is used as a cocatalyst. A linear crystalline polyethylene, an almost fully amorphous, atactic polypropylene, and statistical ethylene-1-octene copolymers containing from 2 to 9 mol

A novel catalyst system containing a complex of Ti4+ with a (O,N,O)-tridentate phenoxyimine ligand and a binary Al(C2H5)2Cl/Mg(C4H9)2 activator at a molar [Al]/[Mg] ratio of 3 affords the synthesis of ethylene polymers with molecular weight in excess of 1 × 106. Ethylene homopolymer produced at 35°C has Mw 2.6 × 106 and ethylene copolymers with small amounts (below 1 mol

Изучены реакции полимеризации этилена, пропилена и сополимеризации этилена с октеном-1 на новом типе пост-металлоценовых катализаторов, осно- ванных на анионе TiCl5 – и комплексах Li+ и K+ с краун-эфиром. Оба комплекса в кристаллическом состоянии сольватированы ацетонитрилом.

The structure and mechanical properties of heterophase compositions based on isotactic polypropylene and ultra-high-molecular-weight polydecene have been studied. The introduction of 20 wt

В настоящее время для синтеза большинства марок полипропилена (ПП) используют каталитические системы Циглера–Натта на основе нанесенных титан-магниевых катализаторов [1]. Известно, что полимер, полученный с использованием алкилалкоксисиланов в качестве внешнего донора представляет собой типичный изотактический ПП [2]. В [3, 4] использовали гетероциклические ароматические азотсодержащие соединения в качестве внешних доноров, что привело к образованию полипропилена с высоким содержанием синдиотактической фракции. Такие полимеры, в отличие от обычных кристаллических полимеров изотактической структуры, обладают эластомерными свойствами.

The influence of external donor nature on propylene polymerization reactions with titanium-magnesium catalyst activated with AlEt3 is studied. The use of cyclohexylmethyldimethoxysilane as the donor increases the content of isotactic polymer and the use of 2,6-dimethylpyridine promotes the formation of syndiotactic component in polypropylene. By combining different donors, it is possible to regulate the site distribution in catalytic system with respect to stereospecificity and to modify stereoregularity, molecular weight characteristics and mechanical properties of polypropylene.

The effect of a cocatalyst in alkene homo- and copolymerizations with transition metal catalysts of different types was studied. The results of studies of polymerizations of ethylene, propylene, and higher linear 1-alkenes and copolymerizations of ethylene with linear 1-alkenes using catalysts of different types in combination with a binary cocatalyst Al(C2H5)2Cl/Mg(C4H9)2 at [Al] : [Mg] > 2.5 were summarized. The traditional Ziegler–Natta catalysts (TiCl4, Ti(Oi-C3H7)4, and TiCl3 ) and titanium postmetallocene complexes with various organic ligands were studied. The binary cocatalyst significantly increased the activity of the traditional catalysts compared with that of Al(C2H5)2Cl and the activity of postmetallocene complexes compared with that of polymethylaluminoxane (MAO). The active centers of these catalytic systems differ in their kinetic parameters, stereospecificity, and copolymerization ability. The efficiency of the Al(C3H5)2Cl/Mg(C4H9)2 cocatalyst can be explained by the in situ formation of finely dispersed MgCl2 and immobilization of the cationic active centers on its surface.

The polymerization of ethylene and propylene and the copolymerization of ethylene and hexene-1 with a Ti(O- iso -Pr) 4 –AlR 2 Cl/MgBu 2 catalyst system have been studied. The advantages of this system over metallocene and postmetallocene catalysts are high activity, low cost, and ease of synthesis. The resulting polymers and copolymers are characterized by a broad molecular-mass distribution, which reflects the heterogeneity of the active sites with respect to kinetic parameters. As a consequence, the ethylene/hexene-1 copolymers exhibit compositional heterogeneity. The active sites of the system produce copolymers with a pronounced tendency toward alternation of monomer units. The propylene polymerization product is mostly amorphous atactic polypropylene.