Aggregation of free chains within a deformed network: A SANS study

Abstract

A reaction, combining labeled oligomers included in an anisotropic matrix, was monitored with small-angle neutron scattering. The initial “butterfly pattern” was strongly enhanced during the reaction, indicating that the growing branched structures are constrained to particular regions within the network. The real-time measurement was continued until the growing clusters had reached their final size. After removal of the constraints the sample completely recovered its original shape. The relaxed isotropic sample exhibits the history of its production bya highly anisotropic scattering pattern. It resembles ellipses whose longer axes are aligned along the stretching direction.