Abstract

I&EC 275

Synthesis of well-defined porous column packings using supercritical CO₂ as the porogenic solvent

Andrew I. Cooper, and Andrew K. Hebb, Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom, Fax: 0044 151 7943588, aicooper@liv.ac.uk

The synthesis of continuous macroporous polymer monoliths for use as separation media is currently a subject of great interest. These materials could have certain advantages over more traditional macroporous polymer bead packings, mainly because of the absence of interstitial voids in the packed state. Recently, we have developed methods for the synthesis of highly cross-linked polymer monoliths using supercritical carbon dioxide as the porogenic solvent (see e.g., A.I. Cooper and A.B. Holmes, Adv. Mater., 1999, 11, 2170). In this paper we describe how it is possible to achieve fine control over average pore sizes and pore size distributions, both by varying the density of the supercritical solvent and also via reverse micellar imprinting. We envisage that well-defined materials of this type might find a number of uses in separation science, particularly in supercritical fluid chromatography.