Synthesis Of Three Polarizable Tetraphenylphenyl Polysiloxane As GC Stationary Phase And Its Chromatographic Performance Evaluation

With many chromatographic researchers’ efforts, Gas Chromatography (GC) has developed into a mature separation technology and been used to separate complex samples in petrochemical industry, food, medicine and other files. In order to expand the application range of GC, it has strong practical significance to synthetize novel excellent stationary phases with good temperature resistance, high column, and high selectivity.This paper includes three ascepts.(1) The development of GC is reviewed, at the same time, the new technology and applications of GC are introduced, including comprehensive two-dimensional gas chromatography (GC X GC), solid-phase microextraction(SPME), high-speed (HSGC), and the new method of using sol-gel prepare capilary column in this work. What’s more, the classification and applications of the stationary phases are described in the paper.(2) The synthesis of three type of polariable tetraphenylcyclopentadienone. The core and key points are as follow. Firstly, the polymethylvinylsiloxane with different content of vinyle (10%,20%, and25%) were prepared at the catalysis of tetramethyl-ammonium using D4and D4vi as raw materials. Secondly,3,4-bis(4-methoxyphenyl)-2,5-diphenyl cyclopentadienone,3,4-bis(4-fluorophenyl)-2,5-diphenyl cyclopentadi-enone, and tetraphenylcyclopentadienone were compounded using1,3-diphenylacet-one and benzil with different substituent. Finally, the first two cyclopentadienone and polysiloxane were added into high temperature diphenyl ether by Diels-Alder reaction. The products whose side chains were methoxyphenyl and fluorophenyl were obtained. Besides, Me2SiCl2and MeViSiCl2were selected as reactants to obtain the molecular weigh dispersion of polymethylvinyisiloxane, after cohydrolytic and polyreaction under the acidic condition. Then, the tetraphenyl-phenyl grafted polysiloxane was gotten by the reaction between polymethylvinyisiloxane and tetraphenylcyclopenta-dienone.It would be specially mentioned that in order to improve the temperature resistance of the new sationary phases, there were a small amount of residual vinyl groups was retained in the sationary phase with the purpose of cross-linking.(3)The evaluation of the new capillary coumns. The three polariable tetraphenyl-phenyl grafted polysiloxane were coated on the inner of capillary columns by the static method. The experiment showed that a good coating ability was obtained when these stationary phases were coated on uninerting columns. At the same time, they possessed high thermal stability, excellent selectivity, and middle polarity. The results of thermogravimetric analysis (TGA) reveabled the decomposition temperature of these three stationary phases were above380℃.(4) The separation of actual samoles. Good results were achieved when the stationary phases were used to separate substituted benzene, polycylic aromatic mixture, aromatics position isomers, and n-alkanes. It was because that the side chain of the new stationary phases we made was tetraphenyl group, which contained a lot of benzene rings could produce dozens of conjugated π bond electron. Thus, the stationary phases would have high polarizability and good selectivity. At the same time, due to the methoxy and fluorin were introduced to polysiloxane, the polarity of them would be further enhanced. The dipole-induced dipole and dispersion would produce between stationary phase and solute molecular, which played an important role in separation. So, the novel stationary phases were suited to polar and weak-polar, especially polycyclic aromatic hydrocarbons (PAHs). They had a wide application prospects in the field of environment monitoring.