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arXiv · 1701.04711

Influence of grafting on the glass transition temperature of PS thin films

Hénot Marceau·Chennevière Alexis·Drockenmuller Eric·Shull Kenneth·Léger Liliane·Restagno Frédéric
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Abstract

We present an investigation of the effect of the interaction between a thin polystyrene film and its supporting substrate on its glass transition temperature (Tg). We modulate this interaction by depositing the film on end-tethered polystyrene grafted layers of controlled molecular parameters. By comparing Tg measurements versus film thickness for films deposited on different grafted layers and films deposited directly on a silicon substrate, we can conclude that there is no important effect of the film-subtrate interaction. Our interpretation of these results is that local orientation and dynamic effects substantial enough to influence Tg cannot readily be obtained by grafting prepolymerized chains to a surface, due to intrinsic limitation of the surface grafting density.

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Hénot Marceau, Chennevière Alexis, Drockenmuller Eric, Shull Kenneth, Léger Liliane, Restagno Frédéric. 2017-01-17. Influence of grafting on the glass transition temperature of PS thin films. https://doi.org/10.1140/epje%2Fi2017-11500-2

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