• 제목/요약/키워드: C18 silica monolith

검색결과 5건 처리시간 0.022초

A New Stationary Phase Prepared from Ground Silica Monolith Particles by Reversible Addition-Fragmentation Chain Transfer Polymerization

  • Lee, Seung-Mi;Zaidi, Shabi Abbas;Cheong, Won-Jo
    • Bulletin of the Korean Chemical Society
    • /
    • 제31권10호
    • /
    • pp.2943-2948
    • /
    • 2010
  • Silica monolith powders were prepared by a new procedure where ground powders of proper size distribution were obtained without sieving. An initiator was attached to this ground monolith and polystyrene was bound by reversible addition-fragmentation chain transfer polymerization to give a new stationary phase. The separation efficiency of this phase was found better than that of the polystyrene bound phase based on conventional silica particles and that of the C18 bound silica monolith powders.

Ground Organic Monolith Particles Having a Large Volume of Macropores as Chromatographic Separation Media

  • Lee, Jin Wook;Ali, Faiz;Kim, Yune Sung;Cheong, Won Jo
    • Bulletin of the Korean Chemical Society
    • /
    • 제35권7호
    • /
    • pp.2033-2037
    • /
    • 2014
  • A reaction mixture was developed for formation of soft organic monolith that was easily smashed, rinsed, refluxed, filtered, and dried to give monolith particles having high pore volume of macropores. This phase was almost without mesopores. The reaction mixture was composed of methacrylic acid, ethylene glycol dimethacrylate, polyethylene glycol (porogen), and an initiator in a mixed solvent of toluene and isooctane. The selection of porogen and its amount was carefully carried out to obtain the optimized separation efficiency of the resultant phase. The median macropore size was 1.6 ${\mu}m$, and the total pore volume was 3.0-3.4 mL/g. The median particle size (volume based) was 15 ${\mu}m$, and the range of particle size distribution was very broad. Nevertheless the column (1 ${\times}$ 300 mm) packed with this phase showed good separation efficiency (N~10,000-16,000) comparable to that of a commercial column packed with 5 ${\mu}m$ C18 silica particles.