硝化棉气凝胶的微结构及热分解特性

摘要

为研究硝化棉（ NC）气凝胶的微结构及其与热性能的关系，用溶胶-凝胶法以及超临界干燥法制备了硝化棉气凝胶。用扫描电子显微镜（ SEM）、X射线衍射（ XRD）、热重-红外联用（ TG-FTIR）表征了其微观结构、结晶性及热性能。结果表明：NC 气凝胶的微观结构为纳米颗粒堆积成的纳米多孔结构。其结晶遭到破坏，呈非晶无序特征。与 NC 相比，NC 气凝胶的 DTG 峰温及 DSC放热峰温度分别提前7℃和11℃，分解热由1429．87 J·g-1提高至1689．21 J·g-1。%To study the microstructure of nitrocellulose( NC)aerogel and its relationship with thermal properties,NC aerogel was prepared by sol-gel method and supercritical drying. The microstructure,crystallizability and thermal properties of the aerogel were characterized by SEM,XRD and TG/DSC-FTIR methods. Results show that:the microstructure of NC aerogel is nano-porous structure accumulated by nano-particles. The crystallization of NC is destroyed in NC aerogel,presenting amorphous disordered state. In comparison with NC,the DTG peak temperature and DSC exothermic peak temperature of NC aerogel shift 7 ℃ and 12 ℃ downwards,respectively,and the decomposition heat increases from 1429.87 J·g-1 to 1689.21 J·g-1.