POLYMERIZATION OF ALPHA-HYDROXYACETYLENES BY TRANSITION-METAL CATALYSTS

alpha-Hydroxyacetylenes (2-propyn-l-ol, DL-3-butyn-2-ol, l-octyn-3-ol, 2-phenyl-3-butyn-2-ol) with a hydroxy functional group were polymeriz ed by various Mo- and W-based catalysts. In general, the catalytic act ivities of Mo-based catalysts were greater than those of W-based catal ysts for these polymerizations. In the polymerization of 2-propyn-l-ol , MoCl5 alone and the MoCl5-EtAlCl2 catalyst system gave a quantative yield of polymer. In the polymerization of 2-propyn-l-ol and its homol ogues by Mo-based catalysts, the polymer yield decreased as the bulkin ess of the substituent increased. On the other hand, the polymer yield increased as the bulkiness of the substituent increased in WCl6-EtAlC l2-catalyzed polymerization. Polymers with a bulkier substituent showe d better solubility in organic solvents than those without a substitue nt [e.g., poly(2-propyn-l-ol)]. The structures of the resulting polyme rs were characterized by various instrumental methods such as H-1- and C-13-NMR, IR, and UV-visible spectroscopies. Thermogravimetric analys es and thermal transitions of the resulting polymers were also studied .