工作场所空气.用1-（9-蒽苯基甲基）哌嗪（MAP）试剂和液相色谱法测定空气中总异氰酸酯基

[中文适用范围]： 本文件规定了工作场所空气中有机异氰酸酯的采样和分析方法。 本文件适用于多种含有异氰酸酯基团的有机化合物，包括单官能异氰酸酯（例如异氰酸苯酯）、二异氰酸酯单体[例如1,6-六亚甲基二异氰酸酯（HDI）、甲苯二异氰酸酯（TDI）、4,4'-二苯基甲烷二异氰酸酯（MDI）和异佛尔酮二异氰酸酯（IPDI）]、预聚物（例如HDI的缩二脲和异氰脲酸酯），以及聚氨酯生产或热分解过程中形成的可色谱分析的中间产物。 在 HDI 和 IPDI 产品的混合体系中，由于 IPDI 单体与 HDI-尿苷二酮共流出，使用本文件不可能识别和量化低含量的 IPDI 单体。 众所周知，该方法低估了基于 MDI 的产品中的低聚物。 与二丁胺滴定相比，基于 MDI 的产品中的总异氰酸酯基团 (NCO) 被低估了约 35%。 该方法已成功修改为使用等度 70% 乙腈/30% 10 mM 甲酸铵流动相与 LC-MS-MS 一起用于 TDI 单体。 该方法的有用范围（以每个样品每种物质的异氰酸酯基摩尔数表示）约为 1 × 10−10 至 2 × 10−7。 使用紫外线 (UV) 检测和荧光 (FL) 检测的单体的仪器检测限约为每个样品 2 ng 单体。 对于 UV 和 FL 检测，使用试剂浸渍过滤器的方法的有用检测限度为每个样品约 10 ng 至 20 ng 单体。 对于 15 l 样品，这对应于 0.7 µg/m−3 至 1.4 µg/m−3。 对于需要固相萃取的吸收器样品，经验表明有用的检测限为每个样品约 30 ng 至 80 ng 单体。 [外文原描述]： This document specifies a method for the sampling and analysis of airborne organic isocyanates in workplace air. This document is applicable to a wide range of organic compounds containing isocyanate groups, including monofunctional isocyanates (e.g. phenyl isocyanate), diisocyanate monomers [e.g. 1,6-hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), 4,4′-diphenylmethane diisocyanate (MDI), and isophorone diisocyanate (IPDI)], prepolymers (e.g. the biuret and isocyanurate of HDI), as well as chromatographable intermediate products formed during production or thermal breakdown of polyurethane. In mixed systems of HDI and IPDI products, it is impossible to identify and quantify low levels of IPDI monomer using this document, due to coelution of IPDI monomer with HDI-uretidinedione. It is known that the method underestimates the oligomer in MDI-based products. Total isocyanate group (NCO) is underestimated in MDI-based products by about 35 % as compared to dibutylamine titration. The method has been successfully modified to be used with LC-MS-MS for TDI monomer using an isocratic 70 % acetonitrile/30 % 10 mM ammonium formate mobile phase. The useful range of the method, expressed in moles of isocyanate group per species per sample, is approximately 1 × 10 −10 to 2 × 10 −7 . The instrumental detection limit for the monomers using both ultraviolet (UV) detection and fluorescence (FL) detection is about 2 ng monomer per sample. The useful limit of detection for the method using reagent impregnated filters is about 10 ng to 20 ng monomer per sample for both UV and FL detection. For a 15 l sample, this corresponds to 0,7 µg/m −3 to 1,4 µg/m −3 . For impinger samples, which require solid phase extraction, experience has shown that the useful limit of detection is about 30 ng to 80 ng monomer per sample.