Laser light-scattering characterization of poly( tetrafluoroethylene) (PTFE) in a perfluoroalkane (perfluorotetracosane) or oligomers of poly(chlorotrifluoroethylene) at temperatures near the crystalline melting point of PTFE and studies of the coil-to-globule transition for polystyrene in cyclohexane are reviewed. Discussions on approach to solving some experimental problems are emphasized. (C) 1993 John Wiley & Sons, Inc.