DYNAMIC BEHAVIOR OF O SOLUTIONS OF POLYSTYRENE INVESTIGATED BY DYNAMIC LIGHT-SCATTERING

Relaxation time distributions from dynamic light scattering (DLS) (obtained from the correlation curves using a Laplace inversion routine REPES), typically covering about 8 decades in relaxation time, have been determined for solutions of polystyrene in cyclohexane at 35 °C (θ conditions) over a wide span of polymer concentrations from very dilute to far into the semidilute regime. The relaxation time distributions increase in complexity with increasing polymer concentration. The results from the semidilute solutions are compared to a theory developed by Brochard and De Gennes and are shown to agree only partially. The results indicate that DLS is a possible tool for the investigation of viscoelastic properties of semidilute polymer solutions. © 1990, American Chemical Society. All rights reserved.