Aqueous emulsion polymerization of substituted acetylenes: Effects of organic solvent and analysis of blue shifts and emulsion polymerization mechanism

摘要

A series of optically active nanoparticles composed of helical substituted polyacetylene is prepared via emulsion polymerization. A specific organic solvent is required for solid substituted acetylene monomers to undergo emulsion polymerization. The effects of this organic solvent are investigated. Its amount is found to be decisive for obtaining stable polymer emulsions. The helical conformations of the substituted polyacetylenes in nanoparticle state are identified with the help of CD and UV-vis spectra. A blue shift occurs in CD and UV-vis spectra of some of the polyacetylene emulsions. The underlying driving force for the blue shift is discussed, and an emulsion polymerization mechanism is proposed.