Detailed Information on Publication Record
2004
Copolymerization of ethene with styrene using CGC catalysts: the effect cyclopentadienyl ligand substitution on the catalyst activity and the copolymer structure
SKEŘIL, Robert, Zdeněk SALAJKA, Pavel ŠINDELÁŘ, Karel MACH, Michal HORÁČEK et. al.Basic information
Original name
Copolymerization of ethene with styrene using CGC catalysts: the effect cyclopentadienyl ligand substitution on the catalyst activity and the copolymer structure
Name in Czech
Kopolymerace etylénu se styrenem pomocí CGC katalytického systému; vliv substituce na Cp ligandu na aktivitu katalyzátoru a vlastnosti kopolymerů
Authors
SKEŘIL, Robert (203 Czech Republic), Zdeněk SALAJKA (203 Czech Republic, guarantor), Pavel ŠINDELÁŘ (203 Czech Republic), Karel MACH (203 Czech Republic), Michal HORÁČEK (203 Czech Republic), Vojtěch VARGA (203 Czech Republic), Ivana CÍSAŘOVÁ (203 Czech Republic) and Jiří PINKAS (203 Czech Republic)
Edition
Journal of molecular catalysis A:Chemical, ELSEVIER, 2004, 1381-1169
Other information
Language
English
Type of outcome
Článek v odborném periodiku
Field of Study
10404 Polymer science
Country of publisher
United States of America
Confidentiality degree
není předmětem státního či obchodního tajemství
Impact factor
Impact factor: 2.316
RIV identification code
RIV/00216224:14310/04:00030760
Organization unit
Faculty of Science
UT WoS
000225606300011
Keywords in English
Titanium; Constrained geometry catalysts; Copolymerization ethenestyrene; Copolymers ethenestyrene; Crystal structures
Tags
Změněno: 10/4/2006 13:53, Mgr. Robert Skeřil, Ph.D.
V originále
The ethenestyrene copolymerization has been investigated using the dimethylsilylene-bridged (amidocyclopentadienyl)dichlorotitanium( IV) complexes [TiCl2{5-1-(SiMe2Nt-Bu-N)-2,3,4-Me3-5-R-C5}], where R=Me (1), H (2), Bu (3), Ph (4), 4-fluorophenyl (5), and but-2-en-2-yl (6) in combination with methylalumoxane (MAO) as catalysts. The nature of the substituent R strongly influenced the catalyst activity and selectivity and the copolymer microstructure and molecular weight. The catalysts derived from 1 to 3 were by about one order more active than those derived from 4 to 6. At the optimum Al/Ti molar ratio of 900, the highly active catalysts produced a pseudo-random copolymer (9597 wt.%) containing up to 47.8 mol% of incorporated styrene. The low-active catalysts gave mixtures of a pseudo-random copolymer (7685 wt.%) with polyethene (10 wt.%) and polystyrene sequences (37 wt.%). The X-ray diffraction crystal structures of 2 and 4 were determined. Comparison of crystal structures of 1 and 2 versus 4 and 5 revealed a slightly shorter distances TiCg (Cg centroid of the cyclopentadienyl ring) and slightly larger ClTiCl angles in 1 and 2, indicating a higher electron density at the titanium atom. An electron attracting effect of phenyl or alkenyl substituents as well as their steric hindrance can account for a low catalytic performance of 46/MAO catalysts.
In Czech
Byla zkoumána kopolymerace etylénu a styrenu pomocí dimethylsilylene-bridged (amidocyclopentadienyl)dichlorotitanium( IV) complexes [TiCl2{5-1-(SiMe2Nt-Bu-N)-2,3,4-Me3-5-R-C5}], kde R=Me (1), H (2), Bu (3), Ph (4), 4-fluorophenyl (5), a but-2-en-2-yl (6). Jako kokatalyzátor byl použit metylaluminoxan (MAO). Povaha substituentu R významně ovlivňovala aktivitu katalytického systému mikrostrukturu kopolymeru a molekulární hmotnost kopolymeru. Katalytické systémy 1 - 3 dosahovaly o řád vyšších aktivit než katalyzátory 4-6. Při optimálním poměru [Al]/[Ti]=900 byl produkován pseudostatistický kopolymer (95-97 wt%) obsahující až 47,8 mol % zabudovaného styrenu. Méně aktivní katalyzátory produkovaly směs pseudostatistického kopolymeru (76-85 wt%) s polyetylénovými (10wt%) a polystyrenovými (3-7wt%) sekvencemi.
Links
| LN00B142, research and development project |
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