QUASI-ELASTIC LIGHT-SCATTERING FROM ENTANGLED POLYMER-SOLUTIONS

The theoretical interpretation of the quasielastic light scattering properties of entangled polymer solutions is discussed. A modified version of the theory of Brochard and deGennes, based on an network with finite lifetime, is found to be in accord with recent experimental results on certain macroion solutions. This leads to the suggestion that an intermediate regime of hydrodynamic properties exists between that concentration corresponding to the onset of entanglements, described by the “congested diffusion” model of Lee et al., and the characteristic concentration defined by Klein in which a cooperative transition to a reptative diffusion mode occurs. The analysis described here appears to have potential for a more detailed interpretation of the hydrodynamic structure of entangled polymer solutions from light scattering experiments. © 1979, American Chemical Society. All rights reserved.