INSTRUMENT TO STUDY SOFT CONDENSED MATTER

Abstract

A simple and inexpensive small-angle light scattering (SALS) instrument for soft condensed matter studies has been developed; the instrument has the advantage of simplicity of equipment, rapid detection and presentation of the entire small-angle pattern for investigation. A wide scattering vector range is achieved using a CCD detector; despite the low-budget components utilized the instrument characteristics have enabled us to obtain high-quality light scattering data from soft matter systems. The setup is especially well suited to studies of systems with a weak scattering power and/or a time-dependent structure evolution in a wide spatial range with sub-micrometer resolution. The technique enabled to measure the size, anisotropy, radial periodicity and internal structure of polymer spherulites at a resolution below that achieved by optical microscopy. Applications of this instrument to investigate the microstructure and spatial correlations in semi-crystalline polymers using the Debye-Bueche theory, and in thermotropic liquid crystalline polymers are also reported. Furthermore, it is demonstrated that the technique is also suitable to study the evolution of microstructure with applied uniaxial tensile strain in thin polymer films.