近红外光谱法快速测定涂料固化剂中游离甲苯二异氰酸酯含量

Determination of Free Toluene Diisocyanate Content in Coating Solidifying Agent by Near Infrared Spectroscopy

用气相色谱分析值为参照,采用近红外透射光谱（NIR）技术采集相应样品的NIR光谱,研究了涂料固化剂中游离甲苯二异氰酸酯（TDI）含量的快速测定分析方法.并从120个固化剂样品中挑选出109个代表性的样品建模,选择7320～ 7250 cm-1和8485～8370 cm-1波段区间,用偏最小二乘法（PLS）和完全交互验证方式建立TDI含量的预测模型.结果表明,固化剂中游离甲苯二异氰酸酯含量和近红外光谱之间存在较好的相关性,其预测模型的校正集均方差（RMSEC）为0.0815,验证集均方差（RMSEP）为0.0715,模型性能良好.近红外光谱法可快速准确测定游离甲苯二异氰酸酯（TDI）含量,用于固化剂样品快速分析.

A rapid determination method of free toluene diisocyanante （TDI） content in coating solidifying agent was developed by near infrared spectroscopy （ NIR）, with GC analysis values as the reference. NIR transmission spectrum of the solidifying agent was first collected. Among the 120 samples analyzed, 109 representative samples were selected to establish TDI between 7320 - 7250 em - 1 and 8485 - 8370 cm - 1, content of predictive models with the NIR wave numbers by the partial least squares （PLS） and fully-interactive authentication methods. The results showed that the free TDI contents in the solidifying agent of and the near- infrared spectra correlate very well. The calibration set RMSEC was 0. 0815 and validation set RMSEP was 0. 0715. This proofed the performance of the working model, and indicated that NIR spectroscopy can be used for fast and accurate determination of TDI content in solidifying agent samples.