Synthesis and Ring-Opening Metathesis Polymerization of Second-Generation Dendronized Poly(ether) Monomers Initiated by Ruthenium Carbenes
نویسندگان
چکیده
The Ring-Opening Metathesis Polymerization (ROMP) of second-generation dendronized monomers is described. Using the highly active and fast-initiating third-generation ruthenium complex [(H2IMes)(pyr)2Cl2RuCHPh], moderate to high molecular weight polymers (430-2230 kDa) are efficiently synthesized with low dispersities (Ð = 1.01-1.17). This study highlights the power of the metathesis approach toward polymer synthesis in a context where monomer structure can significantly impede polymerization. Résumé— La synthèse et la polymérisation par ouverture de cycle par métathèse des monomères poly(éther) de deuxième génération initié par le catalyseur de ruthénium de troisième génération — La polymérisation par ouverture de cycle par métathèse (ROMP, Ring-Opening Metathesis Polymerization) de monomers dendronisés de deuxième génération est décrite. En utilisant le complexe de ruthénium ayant une activité élevée et une initiation rapide de troisième génération [(H2IMes)(pyr)2Cl2RuCHPh], des polymères de masses moléculaires modérées à élevées (430 à 2230 kDa) sont synthétisés de manière efficace avec de basses polydispersités (Ð = 1,01 à 1,17). Cette étude met en évidence la puissance de l’approche de métathèse vers la synthèse de polymères dans un contexte où la structure de monomère peut empêcher de manière significative la polymérisation.
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