Polymeric photosensitizers: effects of intramolecular energy migration on sensitization efficiences

Urruti, E H; Kilp, T

doi:10.1021/ma00131a009

Title: Polymeric photosensitizers: effects of intramolecular energy migration on sensitization efficiences

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Abstract

The occurrence of intramolecular energy migration was found to have no significant effect on the efficiency of ketyl radical formation via hydrogen abstration from cumene by benzophenone (BP) or poly(vinylbenzophenone) (PVBP). Rate constants were found to be 1.1 x 10/sup 6/ and 0.81 x 10/sup 6/ M/sup -1/ s/sup -1/ for the small molecule and the polymer, respectively. The large difference in rate constants, 9.6 x 10/sup 6/ and 22.2 x 10/sup 6/ M/sup -1/ s/sup -1/ for BP and PVBP, respectively, when tetrahydrofuran was used as a quencher is probably attributable to preferential solvation. Conversely, intramolecular energy migration was found to significantly enhance the overall efficiency of triplet energy transfer to 1-methylnaphthalene (MeN). Rate constants for formation of /sup 3/MeN were found to be 0.94 x 10/sup 9/ and 1.85 x 10/sup 9/ M/sup -1/ s/sup -1/ for BP and PVBP, respectively. An energy migration coefficient, LAMBDA, of 3.28 x 10/sup -5/ cm/sup 2/ s/sup -1/ and a frequency of energy migration, omega, of 7.88 x 10/sup 10/ x/sup -1/ were calculated for PVBP. For a series of copolymers of methyl methacrylate with vinylbenzophenone, values of LAMBDA and omega were strongly dependent on the ketone content of the polymermore »« less

Authors:: Urruti, E H; Kilp, T

Publication Date:: Sun Jan 01 00:00:00 EST 1984

Research Org.:: Univ. of Notre Dame, IN

OSTI Identifier:: 7169784

Resource Type:: Journal Article

Journal Name:: Macromolecules; (United States)

Additional Journal Information:: Journal Volume: 17:1

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; METHYLNAPHTHALENES; PHOTOSENSITIVITY; POLYMERS; ENERGY TRANSFER; ABSORPTION SPECTRA; BENZOPYRENE; CUMENE; TETRAHYDROFURAN; ALKYLATED AROMATICS; AROMATICS; CONDENSED AROMATICS; FURANS; HETEROCYCLIC COMPOUNDS; HYDROCARBONS; ORGANIC COMPOUNDS; ORGANIC OXYGEN COMPOUNDS; SENSITIVITY; SPECTRA; 400500* - Photochemistry

Citation Formats


                    Urruti, E H, and Kilp, T. Polymeric photosensitizers: effects of intramolecular energy migration on sensitization efficiences.  United States: N. p., 1984. 
        Web.  doi:10.1021/ma00131a009.

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                    Urruti, E H, & Kilp, T. Polymeric photosensitizers: effects of intramolecular energy migration on sensitization efficiences.  United States.  https://doi.org/10.1021/ma00131a009

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                    Urruti, E H, and Kilp, T. 1984.  
        "Polymeric photosensitizers: effects of intramolecular energy migration on sensitization efficiences".  United States.  https://doi.org/10.1021/ma00131a009.

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@article{osti_7169784,

  title        = {Polymeric photosensitizers: effects of intramolecular energy migration on sensitization efficiences},

  author       = {Urruti, E H and Kilp, T},

  abstractNote = {The occurrence of intramolecular energy migration was found to have no significant effect on the efficiency of ketyl radical formation via hydrogen abstration from cumene by benzophenone (BP) or poly(vinylbenzophenone) (PVBP). Rate constants were found to be 1.1 x 10/sup 6/ and 0.81 x 10/sup 6/ M/sup -1/ s/sup -1/ for the small molecule and the polymer, respectively. The large difference in rate constants, 9.6 x 10/sup 6/ and 22.2 x 10/sup 6/ M/sup -1/ s/sup -1/ for BP and PVBP, respectively, when tetrahydrofuran was used as a quencher is probably attributable to preferential solvation. Conversely, intramolecular energy migration was found to significantly enhance the overall efficiency of triplet energy transfer to 1-methylnaphthalene (MeN). Rate constants for formation of /sup 3/MeN were found to be 0.94 x 10/sup 9/ and 1.85 x 10/sup 9/ M/sup -1/ s/sup -1/ for BP and PVBP, respectively. An energy migration coefficient, LAMBDA, of 3.28 x 10/sup -5/ cm/sup 2/ s/sup -1/ and a frequency of energy migration, omega, of 7.88 x 10/sup 10/ x/sup -1/ were calculated for PVBP. For a series of copolymers of methyl methacrylate with vinylbenzophenone, values of LAMBDA and omega were strongly dependent on the ketone content of the polymer and decreased sharply at 40 mol % VBP or less.},

  doi          = {10.1021/ma00131a009},

  url          = {https://www.osti.gov/biblio/7169784},
  journal      = {Macromolecules; (United States)},
number       = ,

  volume       = 17:1,

  place        = {United States},

  year         = {Sun Jan 01 00:00:00 EST 1984},

  month        = {Sun Jan 01 00:00:00 EST 1984}

}

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