Key points are not available for this paper at this time.
Polymer concentration correlations in a network swollen by a solvent are studied by small-angle neutron scattering. The network is made by statistical cross-linking of long chains in solution. At small scattering vectors, the intensity strongly increases upon swelling. Upon stretching, unusually oriented isointensity lines (``butterflies'') are observed. These effects are well described by a model of fractal heterogeneities of cross-linking giving rise to nonhomogeneous swelling or deformation.
Mendes et al. (Mon,) studied this question.