Preparation Of Polymethyl Siloxane Fused-silica Capillary Chromatographic Column And Utilization

In this paper, the processes of fused-silica capillary chromatographic column using polymethyl siloxane as stationary phase prepared by dynamic coating have been investgated,which studied inert capillary surface treatment technology, stationary phase film and the cross-linking technology. The performance of the prepared column was evaluated through Grob reagents and glycol ether homologue. The results showed that the activity points K+ and Na+ on the surface of silica capillary were removed effectively and the wet ability of capillary was improved through the acid- processing technology. The stationary phase film reacted by free radical reactions through DP cross linker is good uniformity, solvent scouring, symmetrical peak shape. The tailing factor is closed to 100%. The capillary column with high column efficiency, separation properties and thermal stability is prepared by the method.The content of epichlorohydrin was determined in the water phase with the headspace gas chromatography method through self-made silica capillary. The chromatographic condition, the equilibrium time, the equilibrium temperature, sale dosage and the volume ratio of gas-liquid were studied. The results showed that responses of epichlorohydrin in the water phase were highest under the optimized reaction condition:equilibrium time was 20min, the equilibrium temperature was 80℃, adding 7g sodium chloride as salting agen and gas-liquid proportion of 1:1. The concentration of epichlorhydrin in water between 0.001μg/mL and 100μg/mL is in good linear relation. The linear equationy=37.39x+47.79, linear correlation coefficient y=0.9994, the recoveries with standard addition ranged from 93.1% to 102.9%, and the detecting limit was 0.001μg/ml (1ppb). The new method introduced is simple, rapid, accurate, sensitive and effective, which can be adapted to the determination of epichlorohydrin in water with satisfactory results.