基于二维相关中红外光谱技术的邻苯二甲酸二丁酯检测研究

利用二维相关红外光谱技术对正己烷中常用塑化剂邻苯二甲酸二丁酯(DBP)的浓度变化进行了检测研究。利用傅里叶变换红外光谱仪对溶于正己烷中的DBP进行检测,得到742,1 078,1 123,1 281,1 467,1 728,2 873,2 933和2 961cm~(-1)特征吸收峰。将红外光谱分为三个波段400~1 200,1 200~1 900和2 900~4 000cm~(-1),通过二维相关光谱分析技术得知在1 123cm~(-1)波段(苯环面外摇摆及O-—C—O单键伸缩运动)、1 728cm~(-1)(C—O双键的伸缩运动)、2 873和2 961cm~(-1)(CH3伸缩运动)以及3 436cm~(-1)(苯环C—H的面内伸缩运动)对DBP浓度变化比较敏感。结合红外光谱宏观指纹技术以及二维相关光谱分析方法,能够较准确的分析出正己烷中的DBP的浓度变化,为食品中塑化剂含量的检测以及研究塑化剂的迁移规律提供了新的思路和方法。

Determination of Dibutyl Phthalate Based on Two-Dimensional Correlation Mid-Infrared Spectroscopy

As a kind of Phthalate esters (PEs ),Di-n-butyl phthalate (DBP )is widely employed as plasticizers in the pro-duction of polymeric materials.The concentration variation of DBP/n-hexane solution was studied by monitoring the chroma evo-lution of infrared absorption spectra in conj unction with spectral analysis by using two-dimensional-correlation spectroscopy. Absorption peaks at 742,1 078,1 123,1 281,1 467,1 728,2 873,2 933,2 961 cm-1 was gained with Fourier transform in-frared spectra.The IR spectra was divided into three bands:400~1 200,1 200~1 900 and 2 900~4 000 cm-1 ,correlation be-tween the absorption peaks and the sequential order of the changes in spectral intensity extracted from synchronous and asyn-chronous plots indicated that some bong vibrations in 1 123 cm-1 (Benzene ring surface vibration and O—C O bending vibra-tion ),1 728 cm-1 (C—O bending vibration),2 873,2 961 cm-1 (CH3 concertina movement )and 3 436 cm-1 (C—H bending vibration in plane of Benzene)is sensitive to the concentration of DBP.This result showed that the chroma evolution of infrared absorption spectra in conj unction with spectral analysis using two-dimensional-correlation spectroscopy can accurately analyze the concentration of DBP in n-hexane.This research provides a theoretical basis to the detection and analysis of DBP.