Ring-Opening Metathesis Polymerization Of Norbonene Derivatives With Ionic Liquids

Novel monomers of norbornenyl derivatives with the pendant of oligoethyleneoxy group and imidazole-based ionic liquid were synthesized. These monomers were polymerized via ruthenium-catalyzed ring-opening metathesis polymerization。 The polymerizations of all the monomers, like all other poly (norbornene)s synthesized via ROMP, could easily be tested via ~1H NMR spectroscopy. The alkene proton signals of the strained norbornene ring system appeared at 8= 6.0-6.3 ppm. Upon ring-opening and subsequent polymerization, these proton signals shifted upfield to. δ= 5.0-5.5 ppm, and this showed the polymerization was occurred and the monomers had turned to be polymers.The synthesized monomers were polymerized in different solvents: organic solvents and ionic liquid, it was seen that the rate of polymerization was much faster in ionic liquid than in organic solvents; the polymers had high molecular weights using organic solvents, which were much larger than that of calculating values, while conversion of monomers and time have a linear relationship, and number average molecular weight of the polymers with monomer-to-catalyst ratio also have a linear relationship in ionic liquid, but number average molecular weight of the polymers were independent with conversionof monomers. In other words, the polymerization of the synthesized monomers was nonliving both in organic solvents and ionic liquid, but it can becontrolled in ionic liquid while in organic solvents it can't.The compound hept-5-ene-2-carboxylic acid was also polymerized via ring-opening metathesis polymerization, a linear relationship between conversion of monomers and time was observed, but the molecular weights were also much larger than the calculating ones. In the orther words the polymerization of compound hept-5-ene-2-carboxylic acid can't be controlled in ionic liquid.The Polymer has low T_g as measured by DSC, and the polymers were expected to be new polymer electrolytes.