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Free Surface Relaxations of Star-Shaped Polymer Films.

ABSTRACT: The surface relaxation dynamics of supported star-shaped polymer thin films are shown to be slower than the bulk, persisting up to temperatures at least 50 K above the bulk glass transition temperature T_{g}^{bulk}. This behavior, exhibited by star-shaped polystyrenes with functionality f=8 arms and molecular weights per arm M_{arm}

SUBMITTER: Glynos E

PROVIDER: S-EPMC5839106 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Free Surface Relaxations of Star-Shaped Polymer Films.

Glynos Emmanouil E Johnson Kyle J KJ Frieberg Bradley B Chremos Alexandros A Narayanan Suresh S Sakellariou Georgios G Green Peter F PF

Physical review letters 20171128 22

The surface relaxation dynamics of supported star-shaped polymer thin films are shown to be slower than the bulk, persisting up to temperatures at least 50 K above the bulk glass transition temperature T_{g}^{bulk}. This behavior, exhibited by star-shaped polystyrenes with functionality f=8 arms and molecular weights per arm M_{arm}<M_{e} (M_{e} is the entanglement molecular weight), is shown by molecular dynamics simulations to be associated with a preferential localization of these macromolecu ...[more]

PMID: 29286814

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