MEASUREMENT OF NARROW-DISTRIBUTION POLYDISPERSITY USING MULTIANGLE LIGHT-SCATTERING

Molecular radius information obtained with multi-angle laser light sca ttering combined with gel permeation chromatography was used to obtain an upper limit for the polydispersity (M) over bar(w)/(M) over bar(n) of a narrow-distribution polystyrene standard dissolved in toluene. T he radius obtained by light scattering is independent of any other det ector and so is not affected by interdetector delay volumes or interde tector broadening. The value obtained for (M) over bar w/(M) over bar( n) was 1.00096 +/- 0.00004, much closer to unity than previously repor ted. Column broadening was found to be responsible for nearly all the observed peak width.