提出了顶空-气相色谱法测定聚甲基丙烯酸甲酯中甲基丙烯酸甲酯残留量的方法。选择顶空平衡温度和时间分别为90 ℃和30 min。聚甲基丙烯酸甲酯样品经N,N-二甲基乙酰胺溶解后,用HP-INNOWAX色谱柱分离,氢火焰离子化检测器检测。甲基丙烯酸甲酯的质量浓度在1.00~250 mg·L-1范围内与其峰面积呈线性关系,检出限(3S/N)为2.5 mg·kg-1。在3个浓度水平上做回收试验,测得回收率在89.0%~101%之间,测定值的相对标准偏差(n=6)均小于2.5%。

A method of head-space GC for the determination of residual amount of monomer (MMA) of polymethylmethacrylate (PMMA) in its products was proposed. The equilibrium temperature and time of head space were set at 90 ℃ and 30 min,respectively. The PMMA sample was dissolved in N,N-dimethylacetamide, and the analyte was separated on HP-INNOWAX column and detected by FID. Linear relationship between values of peak area and mass concentration of MMA was kept in the range of 1.00-250 mg·L-1 with detection limit (3S/N) of 2.5 mg·kg-1. Tests for recovery were performed by addition of methyl methacrylate standard at 3 concentration levels, results of recovery found were in the range of 89.0%-101% with RSD′s (n=6) less than 2.5%.