建立了涂料中5种挥发性有机物(VOCs)的顶空气相色谱-质谱(HS/GC-MS)分析方法.对溶剂、平衡温度、平衡时间、GC-MS的分离检测等实验条件进行了优化.涂料样品经N,N-二甲基甲酰胺(DMF)-水(1 :1,体积比)溶解分散,经90 ℃、90 min静态顶空后,通过DB-VRX色谱柱分离和质谱检测,外标法定量.结果表明,方法的线性范围为0.013 3 ～6.67 mg/L,5种VOCs的定量下限(LOQ)不高于10 mg/kg,平均加标回收率为82% ～105%,相对标准偏差(RSD)为0.5% ～3.9%.将该法用于市售22种溶剂型涂料和31种水性涂料中5种VOCs含量的测定,部分样品被检出.该方法简单快速、准确灵敏,适用于实际样品中5种VOCs的检测.%A headspace ( HS ) coupled with gas chromatography - mass spectrometric ( GC - MS )method was developed for the determination of 5 residual volatile organic compounds (VOCs) in coating samples. The experimental conditions, such as solvent type, equilibrium temperature and time, as well as the analytical conditions of GC - MS, were optimized. The samples were first dissolved in water- N, N-dimethylformamide (1 ∶ 1, by volume)and treated at 90 ℃ for 90 min, then separated on a DB-VRX capillary column(30 m ×0. 25 mm × 1.4 μm), and determined by GC -MS with the external standard method. The results indicated that the recoveries were in the range of 82％ - 105％with relative standard deviations(RSDs) of 0. 5％ - 3.9％. The linear range of 5 VOCs were in the range of 0. 013 3 -6. 67 mg/L with correlation coefficient no less than 0. 998 9. The limits of quantitation (S/N = 10) were no more than 10 mg/kg. The method was used to determine 5 VOCs in 22 kinds of solvent-based coating and 31 kinds of waterborne coating samples. The result indicated that the proposed method was simple, accurate, rapid and sensitive and could be applied in the rapid analysis of residual VOCs in various coatings.
展开▼
