Elemental Sulfur as Internal Standard for Precise Molecular Weights by Gel Permeation Chromatography

Abstract

Elemental sulfur, when used with polystyrene column packings and tetrahydrofuran as solvent, has been found to be an ideal internal standard for precise molecular weights by gel permeation chromato-graphy. Long-term elution time precision of 0.3% has been achieved with less than optimum operation of chromatographic equipment. Sulfur is inert, elutes reproducibily with a symmetrical peak shape and never interferes with the elution of size-separated materials. The internal standard has a high ultraviolet absorption response and a positive differential refractive index.