“…Conjugated enynes are also attractive candidates to provide unsaturated polymers containing acetylene, diene, and allene moieties by 1,2-, 3,4-, and 1,4-polymerizations, respectively. Although the radical, cationic, and anionic polymerizations of some 4-substituted or 2,4-disubstituted enynes have been reported to proceed through 1,2-polymerization, most of which gave an insufficient information on the polymer structure and the polymerization behavior. Namely, polymers having well-defined structures and molecular weights have not been obtained yet from any conjugated enynes .…”