Measurements of residual strains in ceramic–elastomer composites with diffuse scattering of polarized neutrons

An experiment of diffuse scattering (also referred to as wide-angle neutron scattering) of polarized neutrons with polarization analysis was performed in order to detect residual strains in ceramic–elastomer composites of porous SiO2 and poly(urea–urethane) elastomers. Two ceramics, with pore sizes of 20 and 70 μm, and two elastomers, with hard/soft segments molar ratios of H/S = 0.25 and 1.5, were selected for composite fabrication. The use of polarization analysis made it possible to detect and study very weak coherent scattering peaks from the elastomer synthesized inside SiO2 ceramics. Residual strains were detected and measured based on interatomic distances in the SiO2+ H/S = 1.5 composite but not in the SiO2+ H/S = 0.25. The reason is sought in soft domains being ordered in the H/S = 0.25 elastomer as opposed to the H/S = 1.5 one.