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Sliding friction between an elastomer network and a grafted polymer layer: the role of cooperative effects

Thomas Vilmin·Elie Raphael
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Abstract

We study the friction between a flat solid surface where polymer chains have been end-grafted and a cross-linked elastomer at low sliding velocity. The contribution of isolated grafted chains' penetration in the sliding elastomer has been early identified as a weakly velocity dependent pull-out force. Recent experiments have shown that the interactions between the grafted chains at high grafting density modify the friction force by grafted chain. We develop here a simple model that takes into account those interactions and gives a limit grafting density beyond which the friction no longer increases with the grafting density, in good agreement with the experimental data

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Thomas Vilmin, Elie Raphael. 2004-10-14. Sliding friction between an elastomer network and a grafted polymer layer: the role of cooperative effects. https://doi.org/10.1209/epl%2Fi2004-10451-7

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