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Title: Organometallic polymerization catalysts

Abstract

Well-defined transition metal catalysts have resulted in exciting new opportunities in polymer synthesis. The stereochemistry of vinyl polymers can be rationally controlled with choice of the appropriate catalysts. Studies with optically active catalyst precursors have revealed considerable information on the absolute stereochemistry of olefin polymerization and have led to the synthesis of novel chiral polyolefins. The development of homogeneous olefin metathesis catalysts has also led to a variety of well-defined new polymer structures with controlled molecular weight and molecular weight distribution. Recent advances in understanding the mechanisms and stereochemistry of homogeneous transition metal catalyzed polymerization will be discussed. The ability to control polymer structure through catalyst design presents exciting opportunities in the synthesis of {open_quotes}tailor-made{close_quotes} macromolecules.

Authors:
 [1]
  1. Stanford Univ., CA (United States)
Publication Date:
OSTI Identifier:
142059
Report Number(s):
CONF-930304-
TRN: 93:003688-1752
Resource Type:
Conference
Resource Relation:
Conference: 205. American Chemical Society national meeting, Denver, CO (United States), 28 Mar - 2 Apr 1993; Other Information: PBD: 1993; Related Information: Is Part Of 205th ACS national meeting; PB: 1951 p.
Country of Publication:
United States
Language:
English
Subject:
40 CHEMISTRY; 36 MATERIALS SCIENCE; TRANSITION ELEMENT COMPOUNDS; CATALYTIC EFFECTS; ALKENES; POLYMERIZATION; POLYOLEFINS; STEREOCHEMISTRY; ARCHITECTURE; ORGANOMETALLIC COMPOUNDS

Citation Formats

Waymouth, R.M. Organometallic polymerization catalysts. United States: N. p., 1993. Web.
Waymouth, R.M. Organometallic polymerization catalysts. United States.
Waymouth, R.M. 1993. "Organometallic polymerization catalysts". United States. doi:.
@article{osti_142059,
title = {Organometallic polymerization catalysts},
author = {Waymouth, R.M.},
abstractNote = {Well-defined transition metal catalysts have resulted in exciting new opportunities in polymer synthesis. The stereochemistry of vinyl polymers can be rationally controlled with choice of the appropriate catalysts. Studies with optically active catalyst precursors have revealed considerable information on the absolute stereochemistry of olefin polymerization and have led to the synthesis of novel chiral polyolefins. The development of homogeneous olefin metathesis catalysts has also led to a variety of well-defined new polymer structures with controlled molecular weight and molecular weight distribution. Recent advances in understanding the mechanisms and stereochemistry of homogeneous transition metal catalyzed polymerization will be discussed. The ability to control polymer structure through catalyst design presents exciting opportunities in the synthesis of {open_quotes}tailor-made{close_quotes} macromolecules.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1993,
month =
}

Conference:
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  • Zirconium tetrabenzyl was used as the cocatalyst in olefin polymerization together with MgCl{sub 2}-supported titanium catalysts. Its behavior was compared with those of aluminum and titanium organometallic compounds. In propylene polymerization performed with a MgCl{sub 2}/TiCl{sub 4} catalyst containing ethyl benzoate as the internal donor and with tetrabenzylzirconium as the cocatalyst, a polypropylene with 93 as its isostatic index was obtained, without the need of any external donor. They present a tentative explanation, based on the study of the interaction between the different components of the catalytic system.
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