Eur. Phys. J. B 3, 83-96 (1998)
https://doi.org/10.1007/s100510050286

A neutron reflectometry study of polystyrene network interfaces

¹ Laboratoire Léon Brillouin (CEA-CNRS), CE-Saclay, 91191 Gif-sur-Yvette Cedex, France
² The Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK

Corresponding author: ^a geog@frbr00.physik.uni-freiburg.de

Received: 4 December 1996
Revised: 13 October 1997
Accepted: 23 December 1997
Published online: 15 May 1998

Abstract

We have used neutron reflectometry to measure interfacial widths between two polystyrene films, where either one or both films are crosslinked. The observed interfacial width between two networks is larger than the size expected for “dangling ends”, which suggests motion of heterogeneous regions of the networks. In the case when one of the networks is replaced by a linear polymer, the interfacial profile can be asymmetric with a diffusion “front” of linear polymer penetrating the network to a length scale of up to 200 Å. In the case of a more densely crosslinked network and a high molecular weight linear polymer the interface is symmetric implying negligible penetration.