Premium
Rate constant measurements for initial addition reactions of radicals at the propagation step of photo‐polymerization as studied by pulsed EPR spectroscopy
Author(s) -
Miyake Yusuke,
Marushima Yutaka,
Takahashi Hirona,
Akai Nobuyuki,
Shibuya Kazuhiko,
Kawai Akio
Publication year - 2016
Publication title -
journal of physical organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.325
H-Index - 66
eISSN - 1099-1395
pISSN - 0894-3230
DOI - 10.1002/poc.3566
Subject(s) - chemistry , radical , reaction rate constant , photochemistry , electron paramagnetic resonance , photopolymer , monomer , polymerization , adduct , radical polymerization , radical initiator , spectroscopy , kinetics , polymer , organic chemistry , nuclear magnetic resonance , physics , quantum mechanics
Pulsed EPR spectroscopy was employed to determine reaction rate constants at an early stage of addition reactions in radical polymerizations triggered by four initiator radicals, which were generated by photodissociation of four parent molecules. Two monomers ( tert ‐butylacrylate and tert ‐butylmethacrylate) were examined as reactant. Stern–Volmer analysis on the measured decay time of electron spin echo intensity of reacting radicals provides rate constants for addition reactions . We focused on rate constants for the second step reaction between monomer and adduct radical that is produced by the first step addition reaction between initiator radical and monomer. The rate constant measured by pulsed EPR was evaluated by theoretical calculations in the light of (1) enthalpy difference between product radical and reactants and (2) charge transfer interaction between reacting radical and monomer. Copyright © 2016 John Wiley & Sons, Ltd.