A Scaling Theory of the Competition between Interdiffusion and Cross-Linking at Polymer Interfaces

Achod Aradian; Elie Raphael; Pierre-Gilles de Gennes

doi:10.1021/ma011160d

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A Scaling Theory of the Competition between Interdiffusion and Cross-Linking at Polymer Interfaces

Achod Aradian·Elie Raphael·Pierre-Gilles de Gennes

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Abstract

We study theoretically situations where competition arises between an interdiffusion process and a cross-linking chemical reaction at interfaces between pieces of the same polymer material. An example of such a situation is observable in the formation of latex films, where, in the presence of a cross-linking additive, colloidal polymer particles initially in suspension come at contact as the solvent evaporates, and, optimally, coalesce into a continuous coating. We considered the low cross-link density situation in a previous paper (A. Aradian, E. Raphael, P.-G. de Gennes, Macromolecules 33, 9444 (2000)), and presented a simple control parameter that determines the final state of the interface. In the present article, with the help of simple scaling arguments, we extend our description to higher cross-link densities. We provide predictions for the strength of the interface in different favorable and unfavorable regimes, and discuss how it can be optimized.

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Achod Aradian, Elie Raphael, Pierre-Gilles de Gennes. 2002-02-26. A Scaling Theory of the Competition between Interdiffusion and Cross-Linking at Polymer Interfaces. https://doi.org/10.1021/ma011160d

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