Year: 1977
Type: article
Abstract: Cis ‐transoidal (orange, soluble, and of low crystallinity) and cis ‐cisoidal (red, insoluble, and highly crystalline) polyphenylacetylenes (PPA) were prepared by Ziegler‐Natta catalysts and trans ‐cisoidal (yellow, soluble, and amorphous) polyphenylacetylenes were prepared by using phosphine complexes, TiCl 4 and by thermal initiation. The cis ‐transoidal and cis ‐cisoidal structures isomerize thermally in the solid state above 100°C. In solution the cis ‐transoidal structure isomerizes above 80°C. The polymers obtained by thermal isomerization are soluble, amorphous, and have a trans ‐cisoidal structure. At temperatures higher than 120°C the cis–trans isomerization is accompanied by cyclization and by scission of the polymer chain. A method was developed for determination of cis content of cis ‐transoidal and cis ‐cisoidal polyphenylacetylenes.
Institution: Institutul de Chimie Macromoleculară Petru Poni
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2010223385