An integrated Couette system for in situ shearing of polymer and surfactant solutions and gels with simultaneous small angle x-ray scattering

A Couette cell designed for in situ small angle x-ray scattering (SAXS) studies of polymeric systems under shear is described. Representative results are presented for the effect of shear on the lamellar phase of a concentrated poly(oxyethylene)–poly(oxybutylene) diblock copolymer in aqueous solution. It is shown that the application of shear resulted in a reduction in the lamellar spacing and of the defect density. The former was observed as a shift in the principal peak position in the SAXS pattern, and the latter as an increase in the associated correlation length. It was further shown that the cessation of shear led to a relaxation of both shear induced effects, over a time period of hours.