对位芳纶中间位结构单元含量的定量分析  

Quantitative Analysis of Meta-Aramid Units in

作　　者：孙浩峻 衣小虎 程建华[1,2] 苏朝晖 SUN Hao-Jun;YI Xiao-Hu;CHENG Jian-Hua;SU Zhao-Hui(State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学院长春应用化学研究所,高分子物理与化学国家重点实验室,长春130022 [2]中国科学技术大学,合肥230026

出　　处：《应用化学》2024年第8期1126-1130,共5页Chinese Journal of Applied Chemistry

基　　金：高分子物理与化学国家重点实验室开放基金项目资助。

摘　　要：在聚对苯二甲酰对苯二胺(PPTA)中引入间位结构可以调控其结晶和加工性能,因此确定其中的间位组分含量具有重要的实际意义。本文将PPTA和间位芳纶(PMIA)共混,采集其红外光谱,发现位于689 cm^(-1)处的间位取代苯环的C—H面内振动谱带强度与PMIA的含量呈现良好的线性正比关系,可以检测出共混样品中含有的质量分数2.0%的PMIA。以拉曼光谱分析共混物,利用位于1002 cm^(-1)的苯环呼吸振动谱带作为PMIA的特征峰,建立了峰强度与PMIA含量的标准曲线,具有良好的线性关系,能够检测出样品中低至质量分数0.25%的PMIA。2种方法对比,拉曼光谱法具有更高的准确度和灵敏度,优于红外光谱法。Introduction of meta-aramid units into poly(p-phenylene terephthalamide)(PPTA)allows regulation of its crystallization and processing properties,therefore,quantitation of the meta units in PPTA is of practical importance.In this paper,blends of PPTA with poly(m-phenylene isophthalamide)(PMIA)were prepared and analyzed by infrared and Raman spectroscopies.In the infrared spectra,it was found that the absorption band at 659 cm^(-1) attributed to C—H in-plane wagging vibration of the m-disubstituted benzene ring can be utilized for quantitative analysis of PMIA,the intensity of which exhibited good linear relationship with PMIA content,allowing detection of meta units of 2.0%(mass percent)and above.In the Raman spectra of the blends,the breathing vibration of the meta-disubstituted benzene ring at 1002 cm^(-1) characteristic of PMIA was found to exhibit an intensity proportional to its content with excellent linear correlation,which enabled detection of meta units of a low content of 0.25%(mass percent).In conclusion,the Raman method is more accurate with a lower detection limit,and therefore is superior to the IR method for quantitation of meta units in para-aramids.

关 键 词：芳纶 定量分析 拉曼光谱 红外光谱 

分 类 号：O631[理学—高分子化学]