Radical products of poly(triphenylcarbinol) thermolysis

✍ Scribed by Nikolay M. Shishlov; Shamil S. Akhmetzyanov; Igor V. Novoselov; Galina I. Nikiforova

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 426 KB
• Volume: 198
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1997.021981106

✦ Synopsis

At least three kinds of stable paramagnetic species are formed in films of poly(triphenylcarbinol) 1 upon thermolysis in vacuo up to 500°C. "Low temperature" radicals of triarylmethyl type (RTAMT1) are created in the 120 f 220°C temperature region. These radicals give rise to a symmetric ESR signal (g = 2.0026 0.0003; AH = 1.0 mT) with poorly resolved hyperfine structure and to an absorption band (AB) of allowed transition with A, , = 407 nm in UV spectra. The spectral region of forbidden transitions, assumed for the RTAMT1, is masked by a nonradical AB, in particular by that of quinoid structure of Chichibabin hydrocarbon type with A, , , = 595 nm. From 220°C to 280°C the "high temperature" radicals RTAMT2 appear, with a strong bathochromic shifted AB of forbidden transition ( A, , , = 710 nm). Maximum concentration of RTAMT2 (=lozo spidg) is achieved at =28OoC. Possible structures of both kinds of RTAMT are discussed. At T 2 300°C paramagnetic species that differ from RTAMTare formed in 1.