B. Yamada et al., ESR STUDY OF THE RADICAL POLYMERIZATION OF STYRENE .6. ESR-SPECTRA OFPROPAGATING RADICALS FROM DEUTERATED STYRENES, Polymer bulletin, 38(3), 1997, pp. 339-346
To assign definitely the hyperfine coupling constants for the alpha- a
nd beta-protons of the well-resolved spectrum of poly(styrene) radical
, five types of deuterated styrenes were synthesized and polymerized i
n the cavity of an ESR spectrometer. Their propagating radicals which
presented sufficiently high concentrations were subjected for ESR meas
urement during polymerization in bulk. The spectra obtained exhibited
different splitting patterns depending on the number and positions of
deuteration. The relevant hyperfine coupling constants for the protons
and deuteriums bound to the respective terminal units of the propagat
ing radicals were determined. As a result, the coupling constants for
the alpha- and beta-protons of the poly(styrene) radical, a(alpha) = 1
5.90 G, and a(beta) = 18.30 and 15.90 G, were unambiguously confirmed.