As part of our research on materials for concentrator photovoltaics (CPV), we are evaluating the optical properties and solar radiation durability of a number of polymeric materials with potential CPV application. For optical materials in imaging or non-imaging optical systems, detailed knowledge of the wavelength dependent complex index of refraction is important for optical system design and performance. Here we report the index of refraction, optical absorbance and haze results of various polymers of interest for CPV systems.