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arXiv · 1909.01835

Using Mw dependence of surface dynamics of glassy polymers to probe the length scale of free surface mobility

Yu Chai·Thomas Salez·James Forrest
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Abstract

We describe a series of surface levelling experiments in glassy polystyrene (PS) of varying molecular weight. The evolution through a mobile surface layer is described by the glassy thin film equation that was introduced and used in a previous work. Excellent agreement with the data is achieved, with surface mobility as the single free parameter. Different molecular-weight dependencies in mobility are then observed above and below the glass transition. The results are discussed in terms of surface-chain anchoring in the bulk matrix, and the length scale for surface mobility.

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Yu Chai, Thomas Salez, James Forrest. 2019-09-04. Using Mw dependence of surface dynamics of glassy polymers to probe the length scale of free surface mobility. https://doi.org/10.1021/acs.macromol.9b01728

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