示波极谱法测定聚碳酸酯塑料中双酚A

OSCILLOPOLAROGRAPHIC DETERMINATION OF BISPHENOL A IN POLYCARBONATE PLASTICS

建立了聚碳酸酯塑料中双酚A的示波极谱测定法。聚碳酸酯塑料用蒸馏水浸泡 48h后 ,用二氯甲烷萃取 ,挥干二氯甲烷。样品中的双酚A在 80℃水浴中与硝酸反应生成硝基化合物。该化合物可在示波极谱仪上产生一灵敏的二阶导数吸附波。在 5～ 1 5 0 μg·L-1范围内峰电流与双酚A的含量呈良好线性关系。方法检出限为 2 μg·L-1,相对标准偏差为 0 .9%～ 8.5 % ,试验表明 。

To determine the content of bisphenol A (BPA) in polycarbonate plastics, the sample (20g) was soaked in 200ml of water for 48h to extract the BPA into water. An aliquot of 50ml of the extract was transferred into a separatory funnel and the BPA was further extracted with dichloromethane. The organic phase was transferred to an evaporation dish, and the dichloromethane was removed by evaporation on a water bath of 50℃. The residue in the dish was dissolved in 2ml of water and transferred to a 10ml graduated test tube, and the BPA was reacted with nitric acid at 80℃ in a water bath for 10min to produce nitrated product of BPA. The nitration reaction was stopped by adding ammonia water, the solution was cooled by running water and its volume was maked to 10ml with water. It was found that the nitro compound of BPA gave a sensitive, second derivative adsorptive polarographic wave on the oscillopolarograph, and a linear relationship between peak currents and BPA concentrations was obtained in the range of 5 to 150μg of BPA per liter. Detection limit of the method was found to be 2μg·L -1 and RSD were found to be in the range 0.9% to 8.5%. Through a comparative study of six different samples, and a statistic study by t test, it was concluded that there were no significant differences between the results obtained by the present method and those obtained by the HPLC method.