乌拉草结构及热稳定性研究

Structure and Thermal Stability Study of Carex Meyeriana Kunth

首先采用红外(IR)光谱开展乌拉草结构研究,研究发现:乌拉草IR光谱吸收模式包括νa s CH2-乌拉草、νs CH2-乌拉草、νC=O-乌拉草和νCO-乌拉草,采用变温红外(TD-IR)光谱进一步开展乌拉草热稳定性研究,实验发现:在303~393 K的温度范围内,乌拉草主要官能团(νa s CH2-乌拉草、νs CH2-乌拉草、νC=O-乌拉草和νCO-乌拉草)对应的频率和强度均有明显的改变,乌拉草的热稳定性进一步降低.以乌拉草νCO-乌拉草为研究对象,采用二维红外(2D-IR)光谱,进一步开展乌拉草热变机理研究,实验发现:乌拉草νCO-二维-乌拉草对应的吸收频率包括:1010 cm-1(νCO-1-二维-乌拉草)、1035 cm-1(νCO-2-二维-乌拉草)、1050 cm-(1νCO-3-二维-乌拉草)、1060 cm-(1νCO-4-二维-乌拉草)和1075 cm-(1νCO-5-二维-乌拉草),而随着测定温度的升高,乌拉草νCO-二维-乌拉草吸收峰变化快慢顺序为:1010 cm-1(νCO-1-二维-乌拉草)>1075 cm-1(νCO-5-二维-乌拉草)>1060 cm-1(νCO-4-二维-乌拉草)>1050 cm-1(νCO-3-二维-乌拉草)>1035 cm-1(νCO-2-二维-乌拉草).该研究开拓了三级红外(IR)光谱(包括:IR光谱,TD-IR光谱和2D-IR光谱)在重要的天然植物纤维(乌拉草)结构及热稳定性的研究范围,具有重要的应用研究价值.

The carex meyeriana kunth structure had been studied by infrared(IR)spectroscopy.Theνa s CH2-C a re x Me ye ria na Kunth,νs C H2-C a re x Me ye ria na Kunth,νC=O-C a re x Me ye ria na Kunth,andνC O-C a re x Me ye ria na Kunth were found also.The thermal stability of carex meyeriana kunth could be studied by temperature-dependent infrared(TD-IR)spectroscopy also.With the increase of the temperature(303~393K),the infrared absorption intensity of carex meyeriana kunth(νa s C H2-C a re x Me ye ria na Kunth,νs C H2-C a re x Me ye ria na Kunth,νC=O-C a re x Me ye ria na Kunth andνC O-C a re x Me ye ria na Kunth)had changed obviously,and thermal stability of carex meyeriana kunth was further reduced.The thermal change mechanisation of carex meyeriana kunth was researched respectively by two-dimensional infrared(2D-IR)spectroscopy(νC O-2D-C a re x Me ye ria na Kunth).The band resulting from the carex meyeriana kunthνC O-2D-C a re x Me ye ria na Kunth appeared near 1010 cm-1(νC O-1-2D-C a re x Me ye ria na Kunth),1035 cm-1(νC O-2-2D-C a re x Me ye ria na Kunth),1050 cm-1(νC O-3-2D-C a re x Me ye ria na Kunth),1060 cm-1(νC O-4-2D-C a re x Me ye ria na Kunth),1075 cm-1(νC O-5-2D-C a re x Me ye ria na Kunth)and the sequence of infrared absorption peak changes were 1010 cm-1(νC O-1-2D-C a re x Me ye ria na Kunth)>1075 cm-1(νC O-5-2D-C a re x Me ye ria na Kunth)>1060 cm-1(νC O-4-2D-C a re x Me ye ria na Kunth)>1050 cm-1(νC O-3-2D-C a re x Me ye ria na Kunth)>1035 cm-1(νC O-2-2D-C a re x Me ye ria na Kunth).The study demonstrated the key roles of third-step infrared(IR)spectroscopy(including:IR spectroscopy,TD-IR spectroscopy and 2D-IR spectroscopy)in the analysis of structure and thermal stability of the important natural plant fibre(carex meyeriana kunth)and had important applied research value.