表面活性剂增敏微波等离子体炬原子发射光谱法测定聚烯烃树脂中铜

Determination of copper content in polyolefin resin by microwave plasma torch atomic emission spectrometry through sensitivity enhancement with surfactant

研究了在表面活性剂增敏作用下微波等离子体炬原子发射光谱法(MPT-AES)测定聚烯烃树脂中铜的新方法。对铜测定的仪器工作条件、酸效应及共存元素的影响进行了详细考察。实验结果表明,阳离子表面活性剂(CTMAB)对铜的测定有明显的增敏效果,可使铜的检出限由7.6ng/mL下降为3.1ng/mL,钒、钠、锰、铁、钛等元素的允许量由1倍提高到5倍以上。采用灰化法处理聚烯烃样品,通过工作曲线法测定聚乙烯和聚丙烯中铜的相对标准偏差分别为3.0%和1.9%,加标回收率分别为98%～103%和99%～102%。

A new method was studied of the microwave plasma torch atomic emission spectrometry （MPT-AES） with surfactant sensitization for the determination of copper content in polyolefin resins. The effect of the working conditions of the instrument, acid effect and the co-existing elements on cop- per determination was investigated in detail. The experimental results showed that the surface active agent （CTMAB） has the obvious sensitization effect on the determination of copper. The detection limit of this reaction was found to be decreased from 7.6 ng/mL to 3. lng/mI., the allowance of V, Na, Mn, Fe, Ti and other ions was increased from 1 times to 5 times above. By ashing samples of polyolefin, the relative standard deviations were 3.0 % and 1.9 % in determination of copper in polyethylene and polypropylene by working curve method, and the recoveries were in the range of 98 % to 103 % and 99 % to 102 %.