【摘要】 对甲苯磺酸(p-TsOH)是非氧化性的有机强酸，其对纤维素中半纤维素和低聚糖类等非结晶区成分有较好的选择性降解作用，利用其制备纤维素纳米晶体(CNC),降低了CNC中活性基团酸根基团的产生，显著提高了CNC的热稳定性。在p-TsOH质量分数为60%、温度为70℃、反应时间为4 h的条件下，酸解针叶浆纤维制备了CNC。采用粒度测试仪、透射镜(TEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、热重分析(TGA)和元素分析(EDS-Mappping)对CNC的理化性质进行了表征。结果表明，CNC在悬浮液中表现出良好的稳定性，结晶指数88.43%。CNC平均直径10.25 nm,平均长度400 nm,制备的CNC中只有C、O元素，无S元素，证明在水解过程中p-TsOH只起到催化水解作用。CNC降解温度达到310℃,热稳定性明显提高。通过结晶技术回收p-TsOH,回收率在60%以上。更多还原

【Abstract】 p-toluenesulfonic acid(p-TsOH) is a strong non oxidizing organic acid, which has a good selective degradation effect on the amorphous components such as hemicelluloses and oligosaccharides in cellulose. The cellulose nanocrystals(CNC) with p-toluenesulfonic acidolysis can reduce the generation of acid radical groups and significantly improve thermostability. In this paper, CNC was prepared by acid hydrolysis of coniferous pulp fiber under the conditions of p-TsOH concentration of 60%, temperature of 70 ℃ and reaction time of 4 h. The physical and chemical properties of CNC were characterized by particle size tester, transmission mirror(TEM), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), thermogravimetric analysis(TGA) and analysis of elements by transmission electron microscopy(EDS-Mapping). The results show that CNC has good stability in the suspension, and the crystallization index is 88.43%. The average diameter of CNC is 10.25 nm and the average length is 400 nm. There is no S element in the CNC, and the degradation temperature reaches 310 ℃. The thermal stability is significantly improved, which provides a reference for its application as a composite material.更多还原