Effect of the synthesis conditions of titanium-magnesium catalysts on the composition, structure and performance in propylene polymerization
Journal Title: Polyolefins Journal - Year 2017, Vol 4, Issue 1
Abstract
Supported catalysts synthesized via the interaction of Mg(OEt)2 with TiCl4 in the presence or absence of an internal stereoregulating donor (di-n-butyl phthalate), with different solvents (chlorobenzene, n-undecane, n-heptane) at different titanation temperatures have been studied by a set of physicochemical methods. Data on the chemical composition, X-ray structure and pore structure of these catalysts as well as data on their activity and stereospecificity in polymerization of propylene were obtained. Chemical composition, structure, activity and stereospecificity depend primarily on the presence of an electron donor stereoregulating component and on the solvent nature and titanation temperature. Activity of the catalysts is determined by totality of different characteristics: the chemical composition, in particular, the presence of inactive by-products like TiCl3(OEt), the MgCl2 X-ray structure and pore structure. More active catalyst which was synthesized under optimal conditions in the presence of di-n-butyl phthalate contains the minimal amount of TiCl3(OEt) by-product, and has a more ordered X-ray structure and a homogeneous mesoporous structure with a narrow mesopore size distribution.
Authors and Affiliations
Natalya N. Chumachenko, Vladimir Aleksandrovich Zakharov, Sergey A. Sergeev, Svetlana V. Cherepanova
Influence of annealing on anisotropic crystalline structure of HDPE cast films
High density polyethylene (HDPE) films were produced using cast film extrusion process with different draw ratios, ranging from 16.9 to 148.8. Morphology, crystallinty and orientation state of crystalline and amorphous p...
High porosity polyethylene aerogels
Monolithic aerogels of high molecular weight polyethylene (Mw= 3x106- 6x106 g/mol) have been prepared by solvent extraction with supercritical carbon dioxide from thermoreversible gels prepared in decalin. These low dens...
Intelligent catalysts for ethylene oligomerization and polymerization
Ethylene polymerization catalysts became available in an enormous variety. The challenge in this research is to find catalysts that are able to connect ethylene molecules in such a way that not only linear chains are pro...
Propene-cycloolefin polymerization
Highly active metallocenes and other single site catalysts have opened up the possibility of polymerizing cycloolefins such as norbornene (N) or of copolymerizing them with ethene (E) or propene (P). The polymers obtaine...
Estimation of pyrolysis product of LDPE degradation using different process parameters in a stirred reactor
Pyrolysis of low density polyethylene (LDPE) by equilibrium fluid catalytic cracking (FCC) was studied in a stirred reactor under different process parameters. In this work, the effect of process parameters such as degra...