The influence of thermolysis time on the absorption spectra of partially thermally dehydrochlorinated polyvinyl chloride in acetophenone solution is studied. Strong increase in the optical density D_λ of the dehydrochlorinated PVC samples is caused by the increasing amount N_-C=С- and the length of chains of conjugated double bonds of carbon -C = C-. It is noted that the optical density D_λ first increases linearly with dehydrochlorination time and then reaches saturation. The estimation of amount of double conjugated carbon bonds in 1ml versus thermolysis time t is given, which varies between N_-С=С- = 4·10¹⁷ – 7.4·10¹⁸ for t from 40 to 420 minutes. The effective capture cross section of a photon on conjugated double bonds of carbon for dehydrochlorinated PVC solution in acetophenone is estimated, which was about 10^-17 cm² . The analysis is done of the absorption curves «red» shift to longer wavelengths with growth of N_-С=С- upon increase of thermolysis time. It is noted that the dependence of the optical density on the wavelength in this range is well described by a simple exponential function.

Date Published: 15 December 2015
PDF: 5 pages
Proc. SPIE 9810, International Conference on Atomic and Molecular Pulsed Lasers XII, 98100C (15 December 2015); doi: 10.1117/12.2224963

Published in SPIE Proceedings Vol. 9810:
International Conference on Atomic and Molecular Pulsed Lasers XII
Victor F. Tarasenko; Andrey M. Kabanov; Andrey M. Kabanov, Editor(s)