Full-evaporation Headspace Gas Chromatography for Determination of Methanol Content in Polyvinyl Alcohol

A full-evaporation headspace gas chromatographic method for the determination of methanol content in polyvinyl alcohol is established. Wherein the stationaryphase used was a silica capillary column of 100% dimethylpolysiloxane, nitrogen was used as a carrier gas with a flow rate of 1.0 mL/min, a split ratio of 1∶100, the detect temperature was 200 ℃,inlet temperature, 150 ℃. Headspace sampling was used with an equilibrium temperature of 120 ℃,the equilibrium time of 90 min, and the correlation coefficient r=0.9979.Under these chromatographic conditions, the analytes were well separated, and a good linear relationship existed between peak area of methanol and the detected concentration. The limit of detection was 0.011 mg,the recovery rate was 98.15%. The gas-solid partition coefficient using headspace chromatography was between 0.02~0.4, which was determined by the method of changing the gas and solid ratio. The method accords with the application conditions of the full evaporation headspace gas chromatography. The established chromatographic method is sensitive,accurate,simple,convenient and efficient, which can determine 9 samples simultaneously, and is suitable to determine the methanol content in the mass production of polyvinyl alcohol in factories.