热脱附-气相色谱质谱法测定电子电气产品聚合物材料中多溴联苯和多溴联苯醚

Determination of polybrominated biphenyls and polybrominated diphenyl ethers in polymer materials of electronic and electrical products by gas chromatography-mass spectrometry with thermal desorption

多溴联苯(PBBs)和多溴联苯醚(PBDEs)为持久性的有机污染物,因此对电子电气产品聚合物材料中PBBs和PBDEs含量的测定和控制具有重要意义。以往在对其进行测定前常需先对样品进行前处理,操作较为繁琐或需样品量较大。实验采用热脱附方式将目标化合物从样品中脱附出来进入气质联用仪进行分析,只需mg级别样品量就可实现直接固体进样-气相色谱质谱法(GC-MS)对电子电气产品聚合物材料中PBBs和PBDEs的测定。对热脱附条件包括热脱附温度、热脱附时间、热脱附升温速率等进行了优化,结果表明,在优化的实验条件下,方法线性范围为100~2000 mg/kg,相关系数为0.996以上,方法检出限在5.4~24.8 mg/kg之间,定量限在18.0~82.6 mg/kg之间。按照实验方法对聚丙烯标准物质ERM-EC591中PBBs和PBDEs进行7次平行测定,结果表明,对于含量高于定量限的PBBs和PBDEs,测定值与认定值基本吻合,测定结果的相对标准偏差(RSD)均小于15%。采用实验方法对20批电子电气产品聚合物材料中PBBs和PBDEs进行定性定量分析,并与标准方法GB/T 26125—2011附录A索氏萃取气相色谱质谱法的结果进行比对,结果表明,电子电气产品聚合物材料中PBBs和部分PBDEs的含量都在定量限以下,部分PBDEs的结果与标准方法的相对误差在3.7%~15.7%之间。

Polybrominated biphenyls(PBBs)and polybrominated diphenyl ethers(PBDEs)belong to persistent organic pollutants,so it was of great significance to determine and control the contents of PBBs and PBDEs in polymer materials of electronic and electrical products.In traditional methods,the sample should be pretreated before determination,which was cumbersome or relatively large amount of samples were required.After the target compounds were desorbed from the sample by thermal desorption and analyzed by gas chromatography-mass spectrometry(GC-MS),the determination of PBBs and PBDEs in polymer materials of electronic and electrical products by GC-MS with direct solid injection was realized with only mg-level amount of sample required.The thermal desorption conditions such as thermal desorption temperatures,thermal desorption time and heating rate were optimized.The results showed that the linear range was 100-2000 mg/kg with correlation coefficient higher than 0.996 under the optimized experimental conditions.The limits of detection were between 5.4 mg/kg and 24.8 mg/kg,and the limits of quantification were between 18.0 mg/kg and 82.6 mg/kg.The contents of PBBs and PBDEs in certified reference material of polypropylene(ERM-EC591)were determined for parallel 7 times according to the experimental method.The determination results were basically consistent with the certified values for PBBs and PBDEs when their contents were higher than the limits of quantification.The relative standard deviation(RSD,n=7)was less than 15%.Qualitative and quantitative analysis of PBBs and PBDEs in 20 batches of polymer materials of electronic and electrical products were carried out with the experimental method.The determination results were compared with those obtained by GC-MS with soxhlet extraction in appendix A of standard method of GB/T 26125-2011.The results showed that the contents of all PBBs and partial PBDEs in polymer materials of electronic and electrical products were below the limits of quantification.The relative errors of determination results of other PBDEs with those obtained by standard method were between 3.7%and 15.7%.