Chromatography of Rubber Accelerators and Antioxidants on Silica Gel

Abstract

Abstract The Chromatographic separation on alumina columns of certain components from the acetone extracts of vulcanized rubbers has been reported by Bellamy and coworkers and by Mann. As an adsorbent for such materials, alumina suffers from certain disadvantages, in particular, its tendency to favor chemical change in labile adsorbates. The successful use of silica gel/Celite for the chromatographic separation of a variety of ingredients from propellants and high explosives' suggested that this adsorbent might prove equally useful for the separation of the ingredients of vulcanized rubbers, and this has, in fact, been borne out by recent work in this laboratory. The procedure adopted for the qualitative examination of a rubber extract is as follows. A number of separate portions of the extract (each equivalent to 0.2–0.4 gram of the rubber) are chromatographed on columns of 1 cm. diameter, using a series of different binary solvent mixtures as developers. When the extruded columns have been streaked with appropriate reagents, the positions of the zones, together with the colors of the streaks, give a reasonably unambiguous identification, which can be further confirmed by ultraviolet absorption measurements.