SiO_2/杉木粉复合材料的制备和表征

Preparation and characterization of SiO_2/wood hybrid materials

以人工林杉木粉为原料和正硅酸乙酯(TEOS)为无机前驱体,依据溶剂热法反应原理,采用溶胶凝胶的方法制备了SiO2/木材复合材料。通过红外光谱分析(FTIR)、X射线衍射分析(XRD)、热失重分析(TGA)、扫描电子显微镜分析(SEM)等方法,研究了该复合材料的结构和性能。研究结果表明,使用这种方法,木材的增重率显著提高。木材中的羟基与正硅酸乙酯水解后的羟基发生了缩合反应,体系中存在Si—O—C交联网络,微观上形成了纳米网络结构。木质纤维素的结晶被破坏,结晶度从75.37%(纯木粉)下降到37.42%(木材增重率为78%的复合体系)。交联网络的形成显著提高了该材料的耐热性能,使失重10%时的热分解温度从270℃(纯木粉)提高到409℃。

SiO2/wood hybrid materials were prepared by the method of sol-gel using TEOS as inorganic medium and china fir as raw materials, according to the principle of solvothermal method. The structure and property of the hybrid materials were analyzed by FTIR, XRD, TGA and SEM. The results show that the WPG （weight percent gain） of the wood gets a marked improvement and the hydroxyl groups from the hydrolysis of TEOS reacted with the hydroxyl groups of the wood. In SEM analysis, the network whose size is in nanoscale is found , which resulted from the coagulation of Si-O-C network. And in XRD analysis, the crystalline phase of lignocellulose has been destroyed. Meanwhile, the crystallinity decreases from 75.37% for pure wood powder to 32.42% for 78% WPG hybrid material. TGA shows that the hybrid materials has a better thermostability. The characteristic degradation temperature at 10M mass loss is evidently increased from 270 ℃ for pure wood powder to 409 ℃ for 78% WPG hybrid materials.