Characterization of branched polymers by size exclusion chromatography coupled with multiangle light scattering detector. I. Size exclusion chromatography elution behavior of branched polymers

The elution behavior of branched macromolecules during their separation by size exclusion chromatography (SEC) was studied. The elution behavior of br anched polymers was investigated using samples of randomly branched polysty rene and star branched poly(benzyl methacrylate) of different levels of bra nching by means of a SEC chromatograph coupled with a multiangle light scat tering detector. Abnormal SEC elution behavior was found to be typical for highly branched polymers. After a normal elution at small elution volumes t he molar mass and root mean square radius of the eluting molecules increase d with increasing elution volume. Several SEC experiments were carried out to find explanation for this effect and SEC separation was compared with th e separation by thermal field flow fractionation. (C) 2001 John Wiley & Son s, Inc. J Appl Polym Sci 81: 1588-1594, 2001.