慈竹竹原纤维与黄麻纤维红外及二维相关光谱分析

Analysis of Natural Bamboo Fiber and Jute Fiber with Fourier Transform Infrared Spectroscopy and Two-Dimensional IR Correlation Spectroscopy

以慈竹竹原纤维和黄麻纤维为对象,采用红外光谱法和二维相关红外光谱分析技术,对2种纤维及其化学处理后的单根纤维进行研究。结果表明:慈竹竹原纤维和黄麻纤维的一维红外光谱主要区别于1736cm-1处的CO伸缩振动和木质素苯环特征吸收峰;二者经双氧水-冰醋酸处理后,黄麻单根纤维在1736cm-1附近仍存在明显的吸收峰。在高分辨的二维同步相关谱中,慈竹竹原纤维和黄麻纤维特征差异更为明显,慈竹竹原纤维在1000～1250cm-1范围内有8个自动峰,1008cm-1处强度最大;黄麻纤维有7个自动峰,1217cm-1处强度最大;同时在1435～1750cm-1范围内,黄麻纤维在1726cm-1(C=O伸缩振动)处出现较强的自动峰,而慈竹竹原纤维光谱中没有。各区域内自动峰均为正相关。与化学处理前纤维谱图相比,二者单根纤维的二维相关红外光谱发生了改变,表明纤维成分对其热微扰过程中的变化有一定影响。初步研究表明:二维相关红外光谱为竹原纤维的识别提供了更为丰富的信息,可作为竹原纤维识别的一种新方法。

Two kinds of plant fibers, including natural bamboo fiber made of Neosinocalamus affinis, jute fiber and their single fibers, were analyzed by Fourier Transform infrared （FTIR） spectroscopy and two-dimensional infrared （2D-1R） correlation spectroscopy. Comparing the IR spectra of natural bamboo and jute fibers, we found that the main differences are the peak at around 1 736 cm-lrelated with C =O stretch and the characteristic peaks of lignin. When single fibers were isolated using hydrogen peroxide and glacial acetic acid, the peak at around 1 736 cm-1 also existed in the IR spectra of jute fiber, but the characteristic peaks of aromatic skeletal vibrations were not observed in both IR spectra of single fibers. In addition, the differences were evident in the maps of synchronous 2D-IR correlation spectra of both fibers. In the region of 1 000 - 1250 cm-I, natural bamboo fiber had eight auto-peaks in diagonal line and the highest auto-peak located at 1 008 cm-I But for jute fiber, seven auto-peaks were observed and the highest one was 1 217 cm 1. And there was one auto-peak situated at 1 726 cm-l（C=O stretch）between 1 435 and 1 750 cm-1, which was not observed in natural bamboo fiber. All the auto-peaks were positively correlated. In comparison with the former 2D-IR correlation spectra, the spectra of single bamboo and jute fibers were distinct. It showed that the micro-dynamic changes in the structure of natural bamboo and jute fibers during the min-hearting process were related with the components of fibers. Therefore, this preliminary investigation demonstrated that 2D-IR correlation spectroscopy can become a powerful and new approach to distinguish the natural bamboo fiber from jute fiber.