[en] The ring-opening polymerization of ε-caprolactone has been initiated by [tris(hexamethyldisilyl)amide]yttrium in the presence of an excess of 2-propanol. This initiating system is very active even at high alcohol-to-Y molar ratio. Polymers with controlled molecular parameters (Mn, end groups) and low dispersity are formed as result of fast alkoxide/alcohol exchange. At molar excess of 2-propanol higher than 100, this exchange is no longer quantitative. The in situ formed active species involved in this new initiating system are different from those ones present in the commercial yttrium oxo-isopropoxide Y5(μ-O)(OiPr)13 cluster. Evidence is provided by 1H NMR spectroscopy.
Research center :
Center for Education and Research on Macromolecules (CERM)
Disciplines :
Materials science & engineering Chemistry
Author, co-author :
Martin, Eric; Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Dubois, Philippe ; University of Mons-Hainaut (UMH) > Laboratory of Polymeric and Composite Materials (SMPC)
Jérôme, Robert ; Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Language :
English
Title :
Controlled ring-opening polymerization of epsilon-caprolactone promoted by "in situ" formed yttrium alkoxides
Publication date :
07 March 2000
Journal title :
Macromolecules
ISSN :
0024-9297
eISSN :
1520-5835
Publisher :
Amer Chemical Soc, Washington, United States - Washington