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Study of secondary relaxations of polyethylene by photoluminescence technique

✍ Scribed by T.D.Z. Atvars; E. Sabadini; S.M. Martins-Franchetti

Publisher: Elsevier Science
Year: 1993
Tongue: English
Weight: 490 KB
Volume: 29
Category: Article
ISSN: 0014-3057
DOI: 10.1016/0014-3057(93)90159-d

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✦ Synopsis

Secondary ~, and fl relaxations in polyethylene have been studied by photoluminescence of molecular probes dispersed in the polymer. The temperature of the 7 relaxation of low density polyethylene has been determined as -130°C by the phosphorescence emission of benzophenone. The temperature of the fl relaxation of the same polymer has been found to be -40°C by the fluorescence emission of anthracene. From the differences in the quenching processes for the phosphorescence and fluorescence of the molecular probes, it should be possible to discuss the mechanisms of both the y and fl relaxations depending on the size of the macromolecular segments involved in each process

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