Dynamics of Polymer Solutions. 2. The Determination of Molecular Weight Distribution by Viscoelasticity

Viscoelastic measurements on dilute solutions of large polymer molecules are useful for determining the molecular weight of the largest molecules in a solution. Here we show that it is also possible to get information about the distribution of molecular weights. This can be done either with strain-relaxation data, with stress-relaxation data, or both. We have described such instruments in the preceding paper and elsewhere. Such information is particularly useful for the study of very large DNA molecules, for which other physical techniques are not available.