为了减少由于橡胶促进剂2-巯基苯并噻唑（MBT）掺假而导致橡胶制品质量不过关的问题, 提出利用太赫兹时域光谱技术对MBT的有效含量进行定量研究。利用太赫兹透射测量得到MBT和聚乙烯混合物在0.3THz~1.4THz的吸收特征谱, 提出了一种基于最小二乘支持向量回归（LS-SVR）的MBT定量检测模型, 将LS-SVR模型分别与偏最小二乘模型和支持向量机回归模型进行比较, 得到模型预测集均方根误差分别为1.1330%, 2.5583%和2.3869%。结果表明, LS-SVR的定量模型可取得更好的效果, 其精度更高, 稳定性更好。本研究为MBT定量检测提供了新的快速且有效的方法。

The serious adulteration of the rubber accelerator 2-mercaptobenzothiazole (MBT) will lead to the failure quality of rubber products. Aiming at this problem, a method which uses terahertz time-domain spectroscopy (THz-TDS) was proposed for quantifying the effective content of MBT. The absorption characteristic spectrum of the mixture of MBT and polyethylene in 0.3THz~1.4THz was obtained by terahertz transmission measurement. A MBT quantitative detection model based on least squares-support vector regression (LS-SVR) was proposed. LS-SVR model was compared with partial least squares model and support vector regression model respectively. The results show that, the root mean square errors of the model prediction sets are 1.1330%, 2.5583% and 2.3869% respectively. The quantitative model of LS-SVR can achieve better results with higher accuracy and better stability. This study provides a new fast and effective method for quantitative detection of MBT.