Chapter 8. Structural Techniques at Different Length Scales

Abstract

This chapter details some of the most important techniques routinely implemented for determining the structure of hydrogels and organogels at different length scales, focusing on their application to molecular gels. It will provide the reader with typical examples and situations encountered in the study of gels. The chapter starts with microscopic techniques (optical microscopy, transmission electron microscopy, scanning electron microscopy) that give access to information about large-scale structures (i.e., in the micrometer range). Then, we discuss radiation scattering techniques, such as small angle X-ray scattering, small angle neutron scattering, wide angle X-ray scattering, and quasi-elastic light scattering, that provide information about structures in the submicron range. The chapter ends with a discussion of techniques that are suitable for probing local structures in the nanometer range, such as Fourier-transform infrared spectroscopy, UV–vis absorption spectroscopy, fluorescence, circular dichroism, electron spin resonance spectroscopy, and nuclear magnetic resonance spectroscopy.