Assessing the RAFT Equilibrium Constant via Model Systems: An EPR Study
作者： Wibke Meiser , Michael Buback
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摘要: Reversible addition-fragmentation chain transfer (RAFT) equilibrium constants, K(eq), for the model system cyano-iso-propyl dithiobenzoate (CPDB) - radical (CIP) have been deduced via electron paramagnetic resonance (EPR) spectroscopy. The CIP species is produced by thermal decomposition of azobis-iso-butyronitrile (AIBN). In solution toluene at 70 °C, K(eq) has determined to be (9 ± 1) L · mol(-1). Measurement K(eq) = k(ad)/k(β) between 60 and 100 °C yields ΔE(a) = (-28 ± 4) kJ · mol(-1) as difference in activation energies k(ad) k(β). data measured on are indicative fast fragmentation intermediate addition CPDB.
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