Strain induced alignment of particles in an elastomer host

The properties of composite materials consisting of anisometric nanoparticles dispersed in a host depend on the orientation of the nanoparticles. It is interesting to ask how mechanical strain of the composite affects their orientation. We have carried out experiments stretching both two- and three-dimensional rubber samples containing rigid rod-like particles and measured their orientational order parameter as a function strain. We discuss these results, and make connections with theoretical models.