Volume 38, Number 3, April III 1997
|171 - 176
|Atomic, molecular and optical physics
|01 September 2002
Surface segregation amplification in miscible polymer blends near criticality
Department of Materials Science and Engineering and Laboratory for Research on the Structure of Matter, The University of Pennsylvania - Philadelphia, PA 19104-6272, USA
Accepted: 13 March 1997
In atomic, small molecule or polymeric multicomponent materials, surface compositions naturally differ from the bulk because one component (or phase) will generally favor the surface region. Binary polymer blends represent a model system to investigate surface enrichment because segregation is enhanced by the small combinatorial entropy of mixing and amplified by chain connectivity (relative to small-molecule systems). Therefore, polymers are advantageous systems for probing the thermodynamic complexities underlying surface enrichment in mixtures. In this work, the surface excess of binary polymer blends is studied as a function of composition and temperature in the vicinity of the critical point. Although the surface excess away from criticality behaves as anticipated, it is found to grow slower than expected as criticality is approached from the one-phase region. These results suggest that the surface and bulk thermodynamics are coupled.
PACS: 36.20.-r – Macromolecules and polymer molecules / 68.10.-m – Fluid surfaces and fluid-fluid interfaces / 68.35.Fx – Diffusion; interface formation
© EDP Sciences, 1997
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.