Distribution of chain ends at the surface of a polymer melt: Compensation effects and surface tension

Abstract

AbstractWe consider the surface of a nearly incompressible polymer melt, extending the usual ground‐state analysis of self‐consistent field theory to describe finite length polymers in the ground‐state potential. To maintain self‐consistency, further corrections to the potential are calculated within linear response theory. From this, we find an excess of ends near the surface, followed by a compensating depletion on the Rg length scale, which relies crucially on the finite compressibility of the melt. The attraction of ends to the surface can be described as resulting from a surface potential for ends with a strength on the order of kBT. Our results address the long‐standing controversies of the distribution of chain ends, the chain‐length dependence of the surface tension, and the interaction between objects immersed in a melt. © 1995 John Wiley & Sons, Inc.