Cyclic Guanidines as Efficient Organocatalysts for the Synthesis of Polyurethanes
AMMAR, Yacine Ait
Institut des Sciences Moléculaires [ISM]
Laboratoire de Chimie des Polymères Organiques [LCPO]
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Institut des Sciences Moléculaires [ISM]
Laboratoire de Chimie des Polymères Organiques [LCPO]
AMMAR, Yacine Ait
Institut des Sciences Moléculaires [ISM]
Laboratoire de Chimie des Polymères Organiques [LCPO]
Institut des Sciences Moléculaires [ISM]
Laboratoire de Chimie des Polymères Organiques [LCPO]
CLOUTET, Eric
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 4 LCPO : Polymer Materials for Electronic, Energy, Information and Communication Technologies
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 4 LCPO : Polymer Materials for Electronic, Energy, Information and Communication Technologies
CRAMAIL, Henri
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 2 LCPO : Biopolymers & Bio-sourced Polymers
< Réduire
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 2 LCPO : Biopolymers & Bio-sourced Polymers
Langue
en
Article de revue
Ce document a été publié dans
Macromolecules. 2012, vol. 45, n° 5, p. 2249-2256
American Chemical Society
Résumé en anglais
A systematic survey of basic/nucleophilic organocatalysts for the polyaddition in bulk of polyols, PEG-600, and PTMO-650, to isophorone diisocyanate (IPDI) has been performed. Guanidines were shown to be very efficient ...Lire la suite >
A systematic survey of basic/nucleophilic organocatalysts for the polyaddition in bulk of polyols, PEG-600, and PTMO-650, to isophorone diisocyanate (IPDI) has been performed. Guanidines were shown to be very efficient catalysts for the urethane linkage formation. Bicyclic penta-alkylated guanidines such as MTBD led to polyurethane molecular weight and dispersity that are in the range of those observed with tin-based catalysts such as DBTDL. Tetra-alkylated guanidine such as TBD was shown to be a weaker catalyst as compared to pentaalkylated guanidines, as a result of its high reactivity toward isocyanate, resulting in the formation of a less nucleophilic urea. Although the mechanism has not yet been firmly established, these experiments suggest that a nucleophilic-catalysis mechanism, involving the attack of one of the nitrogen of the guanidine onto the unsaturated system of the isocyanate, should not be totally ruled out with such strong Bronsted base catalysts.< Réduire
Mots clés en anglais
ACTIVATION
ISOCYANATES
LACTIDE
CO2
ORGANIC CATALYSTS
LIVING POLYMERIZATION
CATALYTIC MECHANISMS
RING-OPENING POLYMERIZATION
N-HETEROCYCLIC CARBENES
Origine
Importé de halUnités de recherche