Eur. Phys. J. B 11, 439-444 (1999)
https://doi.org/10.1007/s100510050954

Homogeneous and inhomogenous polyacrylamide gels as observed by small angle neutron scattering: A connection with elastic properties

¹ Laboratoire Léon Brillouin, CEA Saclay, 91191 Gif-sur-Yvette Cedex, France
² Solid State Institute, Technion-Israel Institute of Technology, 32000 Haifa, Israel

Corresponding author: ^a ssgilles@techunix.technion.ac.il

Received: 30 December 1997
Revised: 26 June 1998
Published online: 15 October 1999

Abstract

Small angle neutron scattering of polyacrylamide solutions and gels is presented for different polymer and cross link concentrations. The gels are analyzed in connection with their elastic properties. For less than 11% of polymer concentration and for small cross link contents c_x, it was found that the gels are no more heterogeneous than the solutions. This corresponds to the range of c_x where the elastic modulus increases with c_x. For larger cross link contents when the elastic modulus decreases if c_x increases, the sample appears to be strongly heterogeneous with a large size distribution of the inhomogeneities. The results are compared with the recent model of Oshmyan and Benguigui of the elastic properties of the polyacrylamide gels. Thus a relation can be proposed between the observation of the inhomogeneities by scattering and the mechanical properties