傅里叶变换近红外光谱法应用于聚乙烯树脂的正己烷提取物分析

采用偏最小二乘法(PLS),建立了傅里叶变换近红外漫反射光谱法检测聚乙烯树脂正己烷提取物的数学模型。分析过程选择了最佳光谱预处理方法、谱区范围及主因子数,并使用内部交叉验证对模型进行验证。实验结果表明,当选择最小-最大归一化的光谱预处理方法,谱区范围7 501.8～6 097.9 cm-1和5 025.6～4 597.5 cm-1,主因子数8时定量模型的准确度最好,决定系数(R2)和均方差(RMSECV)分别为0.988和0.416,近红外测定值与标准方法测定值基本一致。对297种牌号共1 251个进口聚乙烯树脂正己烷提取物项目的普查结果表明,聚乙烯树脂正己烷提取物项目的总体安全性较低,属于进口聚乙烯需重点关注的安全卫生项目。

Fourier Transform Near-infrared Spectroscopy of PE Resin used in Analysis of N-hexane Extract

Using partial least squares(PLS)regression to establish mathematical model of n-hexane extract in polyethylene resin by Fourier transform near-infrared spectroscopy.The best spectral pretreatment method,spectral area and main factor number were chose and used internal cross-validation to verify the model in the analysis process.It was found that the result determined by near-infrared spectroscopy coincided with that decided by standard method,when the spectrum pretreatment method was minimum-maximum normalized,spectral range were 7 501.8 cm-1~6 097.9 cm-1 and 5 025.6 cm-1~4 597.5 cm-1,and the main factor number was eight.The correlation coefficients(R2)and root-mean-square error of cross-validation were 0.988 and 0.416 respectively.The survey to n-hexane extract in 1 251 imports polyethylene resin of 297 kinds of grades showed that the item was lower than the overall security,and which should be focused on.