根据烷基酚聚氧乙烯醚(APEO)、直链烷基苯磺酸盐(NABS)及脂肪醇硫酸盐(ALAS) 3种表面活性剂的热裂解特征,提出了热裂解气相色谱质谱法(PGCMS)检测水性涂料中上述3种表面活性剂的方法。水性涂料样品经在120 ℃烘干后粉碎,以正丁醇为溶剂对样品进行超声提取,除去溶剂后烘干,即得到含有表面活性剂组分的样品干膜,此样品供PGCMS分析。样品在600 ℃裂解6 s后,APEO的裂解产物为烷基酚和含有乙氧基单体的化合物;NABS裂解后生成烯烃和烷基苯的同系物;ALAS则裂解生成二氧化硫、烯烃和脂肪醇。根据GCMS分析所得结果,即可对水性涂料中表面活性剂的类型作定性检测。方法的检出限(3S/N)均小于100 mg·kg-1。

Based on their pyrolytic characteristics, category of the 3 surfactants i.e. alkylphenylpolyethylene oxide ethers (APEO), normal alkylbenzene sulfonates (NABS) and apliphatic alcoholic sulfates (ALAS) present in waterthinned coating, was detected by pyrolysisGCMS. The waterthinned coating sample was dried at 120 ℃, crushed and extracted ultrasonically with nbutanol. The extract was evaporated to expel the solvent and dried by heating. The menbraneshaped sample thus obtained was used for GCMS analysis after pyrolysis at 600 ℃ for 6 s. It was shown that the pyrolyzates of APEO were alkylphenols and compounds containing monomer of epoxy group; the pyrolyzates of NABS were olefines and homologues of alkyl benzene; and the pyrolyzates of ALAS were SO2, olefines and aliphatic alcohols. The category of surfactants present in the waterthinned coating can thus be determined from the analytical data found by GCMS. Detection limits (3S/N) found for this method were all less than 100 mg·kg-1.