Synthesis of 1,4-polybutadiene-g-poly(ethylene oxide) via the macromonomer approach by ROMP
Résumé
A poly(ethylene oxide) (PEO) macromonomer end-capped by a polymerizable cyclobutene group has been polymerized by ring-opening metathesis polymerization (ROMP) using Grubbs' second generation (G2) and third generation (G3) catalysts. The macromonomer having a hydrophilic PEO conjugated with a hydrophobic cyclobutene moiety shows self-association properties in water as demonstrated by fluorescence spectroscopy. Therefore, the PEO-based cyclobutene macromonomer was subjected to ROMP both in miniemulsion and in solution. Well-defined 1,4-polybutadiene-g-PEOs with molecular weights ranging from 19 800 to 38 000 g mol(-1) were obtained using G2 in solution with excellent control over molecular weight distribution (PDI = 1.07-1.11).