POLYMERIZATION OF T-BUTYLACETYLENE INITIATED BY TUNGSTEN CARBENE COMPLEX

Polymerization of t-butylacetylene initiated by a tungsten carbene com plex (I) was investigated under various conditions. t-Butylacetylene w as polymerized in high yield in chlorinated hydrocarbons such as CHCl3 and CCl4 and in the presence of AICl(3). The molar mass of the polyme rs formed was as high as 8.2 x 10(4) similar to 3.2 x 10(5). Moreover, when the solution of tungsten carbene complex in CCl4 was irradiated with UV light, the molar mass was remarkably enhanced. This phenomenon may occur because tungsten dichlorocarbene immediately forms. Apparen t rate constants were determined by gas chromatography. NMR spectra sh ow a predominant characteristic of high cis content in the structure o f poly(t-butylacetylene) in contrast to poly(phenylacetylene). The cis content increased ca. 11% when poly(t-butylacetylene) was heated in d ecalin at 110 degrees C. X-Ray diffraction diagrams show that poly(t-b utylacetylene) has an amorphous structure.