热解分离-气相色谱-质谱联用法测定聚苯乙烯电器外壳中20种多溴联苯和多溴联苯醚

将聚苯乙烯(PS)电器外壳样品预先加工制成能通过1mm筛的细颗粒。取此颗粒样品0.5mg置于样品杯中,在裂解仪上从100℃开始,以20℃·min^-1的速率升温至340℃,热解60s,使所测定的20种多溴联苯(PBBs)和多溴联苯醚(PBDEs)热解析出,随即引入DB-1色谱柱,以氦气为载气,在分流进样、程序升温的条件下进行色谱分离,并在电子轰击离子源(EI)和选择离子监测(SIM)模式下进行质谱(MS)测定。上述20种被测物均在100~2000mg·kg^-1内与其对应的峰面积呈线性关系,其检出限(3S/N)均小于15mg·kg^-1。在3个浓度水平上进行加标回收试验,测得回收率在77.9%~119%之间,测定值的相对标准偏差(n=7)均小于20%。按此方法分析了3件实样,并用标准方法GB/T 26125-2011附录A进行对比,结果表明此方法的测定结果与标准方法的测定结果基本一致。

Determination of 20Polybrominated Diphenyls and Polybrominated Diphenyl Ethers in Polystyrene Casings of Electrical Appliances by Pyrolysis-Gas Chromatography-Mass Spectrometry

The sample of polystyrene casing was pretreated by machining to pass through sieve with 1mm mesh,and 0.5mg of the fine sample particles was taken and pyrolyzed in a pyrolyzer at 340℃for 60sby raising the temperature from the initial value of 100℃at a rate of 20℃·min^-1,to liberate the 20polybromo compounds(PBBs and PBDEs)from the polystyrene sample.The PBBs and PBDEs were introduced instantly into DB-1 chromatographic column and separated under the condition of split-flow sample introduction and programed temperature elevation with helium gas as carrier,and then determined by MS with EI ionic source and under SIM mode.Linear relationships between values of mass fractions and peak areas of the 20compounds were found in the same range of 100-2000mg·kg^-1.Detection limits(3S/N)found for these analytes were all less than 15mg·kg^-1.Tests for recovery were made by addition of mixed standard solution at 3concentration levels,giving values of recovery ranged from 77.9%-119%.Values of RSDs(n=7)found were all less than 20%.Three substantial samples were analyzed by this method and checked by the standard method(appendix A of GB/T 26125-2011).Consistent results were found for the two methods.