ABSTRACT
In this chapter we will explore the phenomenon of light scattering from dilute polymer solutions.
Light scattering is an important experimental technique for polymers for several reasons. First, it
provides a direct, absolute measurement of the weight average molecular weight, Mw. Second, it gives information about polymer-polymer and polymer-solvent interactions, through the second
virial coefficient, B (introduced in Chapter 7). Third, under many circumstances light scattering can be used to determine the radius of gyration, Rg (described in Chapter 6) without any prior knowledge about the shape of the molecule (e.g., coil, rod, globule). Fourth, the description of
the scattering process that we will develop in this chapter may be readily adapted to x-ray and
neutron scattering, two other techniques in common use in polymer science. In short, the wealth of
information that may be obtained from light scattering more than justifies the effort we will need to
expend in this chapter to understand how it works. As a final introductory comment, the fact that
light scattering can determine Mw and B tells us that it is a thermodynamic measurement. The fact that it can measure Rg tells us that it is a structural tool as well.
