Effect of temperature during photopolymerization of capillary monolithic columns

Polymeric monolithic capillary columns were synthesized using butyl methacrylate (BMA), ethylene glycol dimethacrylate (EDMA), and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as monomers and 1,4-butanediol, 1-propanol, and water as a porogen mixture. The synthesis was performed over a wide temperature range from -15 degrees C to +70 degrees C using UV radiation to trigger the polymerization process initiated by benzoin methyl ether (BME). The columns exhibited different hydrodynamic properties (permeability) as well as efficiency. The most efficient and the most permeable columns were those polymerized at low temperatures (-15 degrees C to +10 degrees C). The columns photopolymerized at higher temperatures (T > or = 30 degrees C) were completely useless because of low permeability or efficiency. The presented results indicate that temperature can be another factor which allows control of porosity during the preparation of monoliths by photopolymerization.