Synthesis Of Multiphenyl Phenyl Grafted Polysiloxane Containing Cyano And Fluorine And Their Chromatographic Performance Evaluation

Gas Chromatography (GC) has developed into a mature and widely used separation technology and been applied to separate complex samples in petrochemical industry, pesticide, medicine, environmental analysis and other files. In order to expand the application range of GC, it has strong practical significance to synthesis novel excellent stationary phases with good temperature resistance, high column, and high selectivity for the further development and application of GC stationary phases.The side chain of the new stationary phases was tetraphenyl group, which could produce dozens of conjugated π bond electron. Also, the introduction of cyano group, fluorine atom polar substituents on the tetraphenyl phenyl, which greatly increased the polarizabilities of side chain groups of polysiloxane. Based on this, the dipole-induced dipole and dispersive interaction of the new stationary phases with solutes was increased and the separation selectivity of stationary phases for the samples was improvedOur work includes the following aspects:(1) The development of GC, the classification and application of stationary phases is reviewed. The coating of stationary phases, prepration of capillary columns and the evalution of the prepared columns were comprehensive descriped.(2) The synthesis of novel multi-phenyl stationary phases containing cyano group or fluorine atoms. The core and key points are as follow:D4, tetramethylammonium hydroxide as a raw material synthesis catalyst base gum; then the polymethylvinylsiloxane with different content of vinyle (10%,15%, and 20%) were prepared at the catalysis of base gum using D4 and D4Vl as raw materials. Synthesis of the two cyclopentadiene was by condensation, oxidation, cyano substitute reaction. Then, two cyclopentadiene are reaction with polymethylvinylsiloxane at high temperature by Diels-Alder reaction. The products whose side chains were cyanophenyl and fluorophenyl were obtained. 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) Evaluation of capillary columns. The several polariable tetraphenyl-phenyl grafted polysiloxane were coated on the inner of capillary columns by the static method and evaluate its inertia, column efficiency, polarity, temperature resistance, separation performance. The results show high coating efficiency and high column efficiency which suggesting that stationary phases showed good film-forming properties and good column inertness. McReynolds constants suggesting their medium polarity and solvation parameter revealed that dipole-induced dipole, H-bond alkaline and dispersive interaction were the main interaction between solutes and the stationary phases.(4) Separation of the actual sample. Several columns were separated aromatic isomers, monocyclic aromatic hydrocarbons, polycyclic aromatic hydrocarbons and fatty acid esters which obtained better separation effect.