Synthesis And Separation Characteristics Of Fluoro Tetraphenylphenyl Polysiloxane Stationary Phases For Capillary Gas Chromatography

This paper reviews the history of capillary gas chromatography and introduces the classification and application of the polysiloxane gas chromatographic stationary phase, and application of ionic liquids in separation of actual samples. Preparation of elastic quartz capillary column was then described briefly.Research content:mainly research the synthesis of polar fluoro tetraphenylphenyl polysiloxane stationary phases, evaluate its performance and analyze the actual samples. Finally, the separation mechanism is discussed.The specific studies are as follows:1. The preparation of new stationary phases. Firstly, Three polymethylvinylsiloxanes with with different vinyl contents (15%,20% and 25%) were prepared at the catalysis of tetramethyl ammonium hydroxide silicon alkoxide. Then 3,4-di(2,4-difluoro phenyl)-2,5-diphenyl cyclopentadienone and 3,4-di (3,4,5-trifluoro phenyl)-2,5-diphenyl cyclopentadienone were synthesized using 1,3-duphenylacetone and benzil with different substituent. Lastly,3,4-di(2,4-difluoro phenyl)-2,5-diphenyl phenyl polysiloxane (DFPP-15, DFPP-20 and DFPP-25) and 3,4-di(3,4,5-trifluoro phenyl)-2,5-diphenyl phenyl polysiloxane (TFPP-15, TFPP-20 and TFPP-25) were synthesized through Diels-Alder reaction between polymethylvinylsiloxane and 3,4-di(3,4,5-rifluoro phenyl)-2,5-diphenyl cyclopentadienone. specially, in order to improve the temperature resistance of the new stationary phases, a small percentage of vinyl groups was retained in each polymer mixture to facilitate crosslinking.2. The performance evaluation of chromatographic column. The coated fused silica capillary columns with these newly synthesized polymers were evaluated for their column efficiency, polarity, working temperature range and selectivity. Comparing to OV-17 (50% diphenyl,50% dimethyl-polysiloxane), both stationary phases showed easy film-coating ability and excellent selectivity. what is more, polymers of 25% grafted content have a similar polarity to OV-17 and could endure a high temperature up to 360 C.3. Analysis of actual samples. Good selectivity for analyses, including substituted benzene mixtures and polycyclic aromatic hydrocarbons was observed. High polarizability of tetraphenyl-phenyl group strengthened the polarity and selectivity of new stationary phases. Duing to the enhanced dipole-induced dipole interaction and dispersion force with aromatic compounds, these stationary phases have great potential in the analysis of environmental pollutants and is worthy of further development and application.