Synthesis And Properties Of A New Porous Silica Monolith By Template Method And The Application In Liquid Chromatography

Monolithic silica column is the core and motivation of development inchromatography. Monolith column with low column back pressure, high permeability,high mechanical strength，good performance and strong column stability has attractedattentions since1990s,as a new type of chromatography column．It has been widelyused in the fields of medicine, food and health. However, the preparation process isrelatively difficult, until now only a few groups have reported it．Therefore，it isnecessary to find an appropriate method about preparation and modification of themonolithic silica column．The development of the chromatography column was reviewed at first, and thenwe place importance on the points as follows:（1） The preparation of polystyrene microsphere. The polymerizationmicrospheres is prepared by using emulsion polymerization and dispersionrespectively, and then PS microspheres which have monodispersity and diameter of200nm and2.6μm are obtained through the adjustment of the parameters.（2） The optimization of matrix of silica monolith. We used Methyl hydrogensilicone oil(PHMS) and Tetravinyl tetramethylcyelo tetrasiloxane(D4Vi)ascrosslinking monomer, with methyl vinyl siloxane ligand platinum as catalyst tosynthetise silica monolith. We made research into the ratio of PHMS and D4Vi，catalyst content and crosslinking temperature on the influence of the substrate. Thescanning electron microscopy (SEM) and optical images were used to characterize themacroscopic and microscopic structure of the matrix.（3） Preparation of silica monolith with P123as soft template. The silicamonolith was prepared by cross-linking of PHMS and D4Vi,using P123as softtemplate. We make research into the compatibility of P123and the precursorsolution,the template content on the influence of the silica monolith. The scanningelectron microscopy (SEM) and optical images were used to characterize themacroscopic and microscopic structure of the monolith column.（4） Preparation of silica monolith with P123as stiff template. The silicamonolith was prepared by cross-linking of PHMS and D4Vi, using P123as stifftemplate. We make research into the compatibility of PS and the precursor solution,the template content on the influence of the silica monolith. The scanning electronmicroscopy （SEM）, Fourier transform infrared spectrum（FT-IR）and the nitrogenadsorption stripping curve were used to characterize the microscopic structure of themonolith column. （5）Discussion of porous silica monolith chromatography application. Theporous silica monolith is filled in the chromatography column which is long5cm andhas diameter of4.6mm, and then using the obtained chromatographic columnmaterial separation is realized on liquid chromatograph （island sea LC-10AD） totest its separation effect as liquid chromatography column stationary phase.