title: Tailoring the macroporous structure of monolithic silica-based capillary columns with potential for liquid chromatography.
abstract: The present work aims at the optimisation of the synthesis of methyl-silsesquioxane monolithic capillary columns using a sol-gel based protocol. The influence of reaction conditions such as temperature, reaction mixture composition and catalyst concentration has been examined. The morphology of the products was studied by scanning electron microscopy and nitrogen adsorption. Monolithic capillary columns were obtained with a skeleton-like structure with open pores. Pore diameters vary from 0.8 to 15 microm, diameters of the xerogel network vary from 0.4 to 12 microm, respectively. Specific surface areas up to 334 m2/g have been observed, however, many materials did not possess areas above few m2/g which represents the limit of detection of the nitrogen porosimetry measurements. Excellent adhesion to the capillary wall was observed in all cases, and drying was possible at ambient conditions without the formation of cracks.
authors.affiliation: Vienna University of Technology, Institute of Chemical Technologies and Analytics, Getreidemarkt 9/164-AC, A-1060 Vienna, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Laschober
authors.forename: Michael
authors.initials: M
authors.lastname: Sulyok
authors.forename: Erwin
authors.initials: E
authors.lastname: Rosenberg
mesh_terms: D000327:Adsorption; D053801:Capillary Electrochromatography / Q000295:instrumentation* / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D009584:Nitrogen / Q000737:chemistry; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D012822:Silicon Dioxide; D009584:Nitrogen