Synthesis and characterization of copolymers of ethylene and 1-octadecene using the rac-Et(Ind)2ZrCl2/MAO catalyst system

Quijada, R; Narvaez A.; Rojas, R.; Rabagliati F.M.; Galland G.B.; Mauler R.S.; Benavente, R; Perez. E; Perena J.M.; Bello A.

Abstract

The copolymerization of ethylene and 1-octadecene using a bridged metallocene was studied in order to observe the effect of the comonomer on the catalytic activity. A noticeable increase in activity is seen as the concentration of 1-octadecene in the reaction medium increases. 13C NMR analysis shows 6.4 mol-% incorporation of comonomer at the highest 1-octadecene concentration in the feed used here. The molecular weight of the copolymers shows a drastic decrease that may be attributed to chain termination by transfer or ?-elimination of the comonomer. As to the molecular weight distribution, it remains within a narrow range, as expected with metallocene catalysts. The melting temperature and the enthalpy of melting of the copolymers show a decrease with increasing comonomer content. As usual for ethylene copolymers, the X-ray crystallinities are higher than those determined from the enthalpy of melting. © Wiley-VCH Verlag GmbH, 1999.

Más información

Título de la Revista: MACROMOLECULAR CHEMISTRY AND PHYSICS
Volumen: 200
Número: 6
Editorial: WILEY-V C H VERLAG GMBH
Fecha de publicación: 1999
Página de inicio: 1306
Página final: 1310
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-0000356687&partnerID=q2rCbXpz