Elasticity dominated surface segregation of small molecules in polymer mixtures

Krawczyk, J.; Croce, S.; McLeish, T.C.B.; Chakrabarti, B.

Abstract

We study the phenomenon of migration of the small molecular weight component of a binary polymer mixture to the free surface using mean field and self-consistent field theories. By proposing a free energy functional that incorporates polymer-matrix elasticity explicitly, we compute the migrant volume fraction and show that it decreases significantly as the sample rigidity is increased. A wetting transition, observed for high values of the miscibility parameter can be prevented by increasing the matrix rigidity. Estimated values of the bulk modulus suggest that the effect should be observable experimentally for rubberlike materials. This provides a simple way of controlling surface migration in polymer mixtures and can play an important role in industrial formulations, where surface migration often leads to decreased product functionality.

Citation

Krawczyk, J., Croce, S., McLeish, T., & Chakrabarti, B. (2016). Elasticity dominated surface segregation of small molecules in polymer mixtures. Physical Review Letters, 116(20), Article 208301. https://doi.org/10.1103/physrevlett.116.208301

• Journal Article Type: Article
• Acceptance Date: Apr 27, 2016
• Online Publication Date: May 18, 2016
• Publication Date: May 18, 2016
• Deposit Date: Apr 29, 2016
• Publicly Available Date: May 19, 2016
• Journal: Physical Review Letters
• Print ISSN: 0031-9007
• Electronic ISSN: 1079-7114
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 116
• Issue: 20
• Article Number: 208301
• DOI: https://doi.org/10.1103/physrevlett.116.208301
• Public URL: https://durham-repository.worktribe.com/output/1413561
• Related Public URLs: http://arxiv.org/abs/1509.07311