微波辅助固相顶空-气相色谱法直接测定乙烯-醋酸乙烯共聚塑料中的苯乙酮

通过微波无溶剂提取与顶空气相色谱在线联用,建立了一种可直接快速检测固体样品中挥发性成分苯乙酮的方法,考察了微波加热时间对灵敏度和重现性的影响.苯乙酮峰面积随微波加热时间的延长呈现先增加后减小的趋势,短时间微波辐射下苯乙酮峰面积的重现性优于长时间微波辐射.本方法的线性范围为0.003～0.333 mg/g;检出限为2.022 μg/g.与常规加热的顶空气相色谱法相比,本方法简便、省时、重现性好.对苯乙酮与共存物峰面积比随时间变化的研究结果表明,短时间微波加热有利于实现极性组分的选择性提取.

Direct Determination of Acetophenone in Ethylene Vinyl Acetate Plastic by Microwave Assisted Solid Headspace-Gas Chromatography

A new method of microwave-assisted solid phase headspace-gas chromatography was deve-loped for the direct determination of volatile components in solid samples.The effects of microwave irradiation time on sensitivity and reproducibility were investigated.Ethylene vinyl acetate(EVA) plastic was directly used as sample without any pretreatment and the content of acetophenone was rapidly determined using the proposed method.The peak area of acetohenone was increased firstly and then decreased with the increasing of microwave irradiation time.The reproducibility of peak area was better under short microwave irradiation time than that under long one.Linearity range and detection limit for acetophenone were 0.003-0.333 mg/g,2.022 μg/g respectively.In comparison with the results using conventional headspace-gas chromatography revealed that the proposed method was time-saving and had better reproducibility.Additionally,effects of heating time on the peak area ratio of acetophenone and coexistent compound were also studied.The result showed that the extraction selectivity of polar compounds was better under short microwave irradiation time than that under long one.