Light Scattering and its Applications in Polymer Characterization

In this chapter, we emphasize on the principles in which light scattering methods are founded and apply these to different systems. We also stress the importance of a solid 

Unfortunately, because of space, we have not covered important new developments in light scattering for the study of nontransparent systems such as diffusion wave spectroscopy (DWS), fiber-optic quasi-elastic light scattering (FOQELS), dual-color cross-correlation, 3D crosscorrelation DLS, and improved techniques followed from these techniques [1-4]. 

In the first section, we introduce the general theory of light scattering. The second section is devoted to SLS, and we give some examples of its application. In the third section, we discuss the principles of DLS and we apply these to the study of the dynamics of different systems, whether dilute or concentrated solutions. 

Let us consider an electromagnetic field incident on a small volume element on the order of where X is the wavelength of light in the material (solution, particle suspension, etc.) due to the imbalance of the molecules that enter and leave such volume, there will be fluctuations in density, concentration, and others that concomitantly will produce fluctuations in the local dielectric constant. Let us denote by Ae(R, t) the deviation of the dielectric constant from its mean (e at R and time t. Since these 

Handbook of Polymer Synthesis, Characterization, and Processing, First Edition. Edited by Enrique Saldivar-Guerra and Eduardo Vivaldo-Lima. 2013 John Wiley Sons, Inc. Published 2013 by John Wiley Sons, Inc. 

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