Heterogeneity of Active Sites of Ziegler-Natta Catalysts: The Effect of Catalyst Composition on the MWD of Polyethylene Full article
| Journal |
Journal of Applied Polymer Science
ISSN: 0021-8995 , E-ISSN: 1097-4628 |
||
|---|---|---|---|
| Output data | Year: 2010, Volume: 115, Number: 4, Pages: 2432-2439 Pages count : 8 DOI: 10.1002/app.31359 | ||
| Tags | Computer modeling, Gel permeation chromatography (GPC), Molecular weight\mass distribution, Polyethylene (PE), Ziegler-Natta catalysts | ||
| Authors |
|
||
| Affiliations |
|
Abstract:
Experimental data on the molecular weight distribution (MWD) of polyethylene (PE) produced over a broad number of Ziegler-Natta catalysts differing in composition and preparation procedure are presented. These catalysts include nonsupported TiCl3 catalyst, four types of supported titanium-magnesium catalysts (TMC) differing in the content of titanium and the presence of various modifiers in the composition of the support, and a supported catalyst containing VCl4 as an active component instead of TiCl4. The studied catalysts produce PE with different molecular weights within a broad range of polydispersity (Mw/Mn = 2.8–16) under the same polymerization conditions. The heterogeneity of active sites of these catalysts was studied by deconvolution of experimental MWD curves into Flory components assuming a correlation between the number of Flory components and the number of active site types. Five Flory components were found for PE produced over nonsupported TiCl3 catalysts (Mw/Mn = 6.8), and three–four Flory components were found for PE produced over TMC of different composition. A minimal number of Flory components (three) was found for PE samples (Mw/Mn values from 2.8 to 3.3) produced over TMC with a very low titanium content (0.07 wt %) and TMC modified with dibutylphtalate. It was shown that five Flory components are sufficient to fit the experimental MWD curve for bimodal PE (Mw/Mn = 16) produced over VMC.
Cite:
Nikolaeva M.I.
, Mikenas T.B.
, Matsko M.A.
, Echevskaya L.G.
, Zakharov V.A.
Heterogeneity of Active Sites of Ziegler-Natta Catalysts: The Effect of Catalyst Composition on the MWD of Polyethylene
Journal of Applied Polymer Science. 2010. V.115. N4. P.2432-2439. DOI: 10.1002/app.31359 WOS Scopus РИНЦ ANCAN OpenAlex
Heterogeneity of Active Sites of Ziegler-Natta Catalysts: The Effect of Catalyst Composition on the MWD of Polyethylene
Journal of Applied Polymer Science. 2010. V.115. N4. P.2432-2439. DOI: 10.1002/app.31359 WOS Scopus РИНЦ ANCAN OpenAlex
Dates:
| Submitted: | Jun 3, 2009 |
| Accepted: | Aug 30, 2009 |
| Published online: | Oct 14, 2009 |
| Published print: | Feb 15, 2010 |
Identifiers:
| Web of science: | WOS:000272893400064 |
| Scopus: | 2-s2.0-73849119267 |
| Elibrary: | 15316925 |
| Chemical Abstracts: | 2009:1438322 |
| Chemical Abstracts (print): | 152:145143 |
| OpenAlex: | W2039321992 |