Synthesis and characterization of a liquid crystalline polyacetylene with cholesteryl side groups using Schrock-type molybdenum initiators

✍ Scribed by Sebastian Koltzenburg; Franz Stelzer; Oskar Nuyken

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 113 KB
• Volume: 200
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/(sici)1521-3935(19990401)200:4<821::aid-macp821>3.0.co;2-a

✦ Synopsis

We report the synthesis and polymerization of a new acetylene monomer with a cholesteryl side group. The monomer shows monotropic behaviour. Polymerization is initiated with the well-defined Schrock-type molybdenum carbene Mo(CHR)(NAr)(OR9) 2 with NAr = 2,6-dimethylaniline, R = C(CH 3 ) 2 C 6 H 5 and R9 = C(CH 3 )(CF 3 ) 2 . Polymerization is almost quantitative and yields a polymer with a comparatively narrow molecular weight distribution. The material is an orange solid which is soluble in common organic solvents at room temperature. The results of DSC, X-ray diffraction, and polarizing optical microscopy (POM) indicate that, upon cooling, the polymer exhibits a mesophase of the smectic A type before undergoing a glass transition.