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pro vyhledávání: '"Marvin L. Poutsma"'
Autor:
Marvin L. Poutsma
Publikováno v:
The Journal of Physical Chemistry A. 120:4447-4454
Recently, we presented structure-reactivity correlations for the gas-phase rate constants for hydrogen abstraction from sp(3)-hybridized carbon by three electrophilic radicals (X(•) + HCR3 → XH + (•)CR3; X = Cl(•), HO(•), and Br(•)); the
Autor:
Marvin L. Poutsma
Publikováno v:
The Journal of Physical Chemistry A. 120:183-190
Recently we presented structure-reactivity correlations for the gas-phase ambient-temperature rate constants for hydrogen abstraction from sp(3)-hybridized carbon by chlorine atom and hydroxyl radical (Cl•/HO• + HCR3 → HCl/HOH + •CR3); the re
Autor:
Marvin L. Poutsma
Publikováno v:
Journal of Analytical and Applied Pyrolysis. 92:25-42
Thermolysis of tetrafluoroethylene at ≤500 °C is well-known to lead to equilibration with octafluorocyclobutane; at ≈600 °C this mixture forms hexafluoropropylene; and at slightly more forcing conditions the latter is converted to octafluoroiso
Autor:
Marvin L. Poutsma
Publikováno v:
The Journal of Organic Chemistry. 76:270-276
Chemical intuition suggests that the stabilization of a carbon-centered free radical by a substituent X would be the greatest for a prim and least for a more stable tert radical because of "saturation". However, analysis of a comprehensive recent set
Autor:
Marvin L. Poutsma
Publikováno v:
Polymer Degradation and Stability. 94:2055-2064
Formation of the radical precursor to trimer (T) during pyrolysis of polystyrene features a 1,5-hydrogen shift. However because 1,3-shift is so much slower, the sources of the less abundant dimer (D) and tetramer (Te) remain unclear. While we and oth
Autor:
Marvin L. Poutsma
Publikováno v:
Journal of Physical Organic Chemistry. 21:758-782
The performance of different models for the influence of enthalpy and polar effects on the activation energies for liquid-phase addition of carbon-centered radicals to terminal olefins is compared for the extensive data set from the Fischer group, su
Autor:
Marvin L. Poutsma
Publikováno v:
Journal of Analytical and Applied Pyrolysis. 80:439-452
Mechanisms for pyrolysis of poly(α-methylstyrene) must rationalize high selectivity for monomer formation, negligible formation of volatile oligomers, and notably slow decrease in molecular weight compared with the rate of weight loss, i.e., unzippi
Autor:
Marvin L. Poutsma
Publikováno v:
Polymer Degradation and Stability. 91:2979-3009
Simulations of the initial distribution of volatiles from pyrolysis of polystyrene were based on propagation rate constants estimated by thermochemical kinetic procedures. The voluminous database exhibits a disturbing lack of consistency with respect
Autor:
Marvin L. Poutsma
Publikováno v:
Journal of Analytical and Applied Pyrolysis. 73:159-203
Two models for formation of volatile n-mers from pyrolysis of polyisobutylene at mild conditions are compared: the random scission model of Lehrle and the back-biting model of Sawaguchi, each having a competitive unzipping component to form monomer.
Autor:
Marvin L. Poutsma
Publikováno v:
Chemical Physics Letters. 654:139-140
The recently proposed term “radicalicity” was described as a measure of the reactivity of a free radical Q , i.e., a kinetic quantity. It is shown here that in fact it is simply a frame-shifted version of the well-known bond dissociation energy,