何秀芬+陈歆+何燕+汤建彪

摘 要 建立了一种使用近红外光谱技术即时测定浓缩天然胶乳干胶含量的方法。以国家标准方法测定天然胶乳的干胶含量作为标准值，用偏最小二乘法（PLS）建立近红外光谱与天然胶乳干胶含量的多元信号校正模型，并使用内部交叉验证及外部验证集验证评价模型，对天然胶乳中干胶含量进行测定对比分析。结果表明，模型相关系数达0.977 8，模型的预测均方差为0.105，交叉验证均方差为0.106，说明该模型具有较高的预测水平。通过F检验和t检验进一步对比模型检测值和国标法检测值，2种方法的分析结果差异不显著性。近红外光谱技术测定浓缩天然胶乳干胶含量准确度、精确度良好，可应用于实际生产与交易中的快速检测。

关键词 浓缩天然胶乳 ；近红外光谱检测 ；干胶含量

中图分类号 TQ331 文献标识码 A Doi：10.12008/j.issn.1009-2196.2017.09.014

Determination of Dry Rubber Content in Concentrated Natural Latex

by Near Infrared Spectroscopy

HE Xiufen1） CHEN Xin2） HE Yan1） TANG Jianbiao1）

（1 Analysis & Testing Center， CATAS， Haikou， Hainan 571101

2 Environment and Plant Protection Institute， CATAS， Haikou， Hainan 571101）

Abstract A method for real-time determination of the content of concentrated natural latex was developed by using near infrared spectroscopy. The dry rubber content in concentrated natural latex was determined by using the national standard method as reference， the values of which were used to establish a model between the signals of the near infrared and the dry rubber contents using the partial least squares （PLS） method. This model was evaluated through internal and external cross validations. The results showed that this model had a correlation coefficient of 0.9778 with a root mean squared error of prediction （RMSEP） being 0.105 and a root mean standard error cross validation （RMSEVC） being 0.106. This indicated that the model was good for evaluation. The values from the model and the national standard method were compared by using the F-test and T-test， and no significant difference was observed between these two methods. The method using near infrared spectroscopy for determination of dry rubber content was fast and accurate， which could be applied for rapid determination of concentrated natural latex in the natural rubber production and trade sectors.

Keywords concentrated natural latex ； near infrared spectroscopy ； dry rubber content

天然膠乳是各种军用、民用胶乳制品不可缺少的原料，是我国质检部门强制法检的商品之一，也是国际贸易中十分关注的商品[1-2]。浓缩天然胶乳的主要成分是橡胶颗粒（干胶含量）、非橡胶颗粒和乳清[3]，其中，干胶含量决定着浓缩天然胶乳的质量，也是决定其经济技术指标的主要因素。因此，对天然浓缩胶乳中干胶含量进行快速检测，在橡胶生产、市场贸易中具有十分重要的意义。

目前，检测干胶含量的方法有多种，国内常使用的有国家标准方法（GB/T 8299-2008），烘箱干燥法、真空干燥法[4]、热量测定法[5]、荧光法[6]、超声法[7]、热辐气动法[8]、微波测量法[9]和电容传感器[10]等。……