微波辅助萃取-气相色谱-质谱法测定丙烯酸树脂中9种残余单体

Determination of 9 residual acrylic monomers in acrylic resins by gas chromatography-mass spectrometry coupled with microwave assisted extraction

建立了丙烯酸树脂中9种残余单体(丙烯酸甲酯、丙烯酸乙酯、甲基丙烯酸甲酯、甲基丙烯酸乙酯、丙烯酸丁酯、甲基丙烯酸丁酯、苯乙烯、丙烯酸、甲基丙烯酸)的微波辅助萃取-气相色谱-质谱检测方法。固体丙烯酸树脂样品用乙酸乙酯微波萃取后加甲醇沉淀(液态丙烯酸树脂样品直接用甲醇稀释)后,采用DB-WAX毛细管柱分离。结果表明,本方法在20 min内同时分离了9种单体,所测物质的定量限(LOQ,以信噪比为10计)为3～50 mg/kg(固体树脂)和1～10 mg/kg(液态树脂);在1～500 mg/L范围内,线性相关系数均在0.995以上;在5个添加水平下平均回收率为84.4%～108.6%,相对标准偏差(n=6)为0.27%～4.97%。方法的灵敏度和回收率高、选择性好,能满足实际工作的要求。

A reliable gas chromatography-mass spectrometry （GC-MS） method was developed for the determination of 9 residual acrylic monomers （methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl acrylate, butyl methacrylate, styrene, acrylic acid and methacrylic acid） in acrylic resins. Solid resin was precipitated with methanol after microwave assisted extraction with ethyl acetate for 30 rain, and liquid resin was diluted with metha- nol directly. The nine acrylic monomers got a good separation within 20 rain on a DB-WAX column. The limits of quantification （ LOQs, S/N = 10） of the method were in the range of 1- 10 mg/kg for liquid resin and 3 -50 mg/kg for solid resin. The calibration curves were linear within 1 -500 mg/L range with correlation coefficients above 0. 995. The recoveries ranged from 84.4% to 108.6% at five spiked levels. The sensitivity, recovery and selectivity of the method can fully meet the requirements of practical work.