微米级硝化纤维素的制备及性能研究

为了使硝化反应在近似均相的条件下进行,采用对精制棉进行水解处理,用稀酸水解法制得结晶度较为一致的微晶纤维素,再用硝硫混酸进行硝化得到微米级硝化纤维素。用扫描电镜和红外光谱对其微观形貌和结构进行了表征。用DSC分析了其热性能,并测试了其撞击感度和黏度。结果表明,制备微米级硝化纤维素的最佳条件为:硝硫混酸体积比为1∶3,硝化时间30min,硝化温度为35℃。制得的微米级硝化纤维素样品粒度均匀,其特性落高为57.466cm,黏度为478mPa·s,分解峰温达到211.20℃,硝化均匀,含氮量可达12.8%。

Study on the Preparation and Properties of Micron Nitrocellulose

To make nitrification reaction perform in an approximate homogeneous condition,the microcrystalline cellulose with uniform crystallinity was prepared by hydrolysis treatment of refined cotton and dilute acid hydrolysis method.Then micron nitrocellulose was prepared via nitrification using mixed acid of nitric acid/sulphuric acid.The microtopography and structure of micron nitrocellulose were characterized by SEM and FTIR,the thermal property was analyzed by DSC,and the impact sensitivity and viscosity were tested.The results show that the optimum conditions for preparing micron nitrocellulose are determined as: the volume ratio of mixed acid of nitric acid/sulphuric acid as 1:3,nitrification time 30min,and nitrification temperature 35℃.The granularity of prepared micron nitrocellulose samples is uniform,and with characteristic drop height of 57.466cm,viscosity of 478mPa·s,and decomposition peak temperature of 211.20℃.Its nitrificaion is uniform,and the nitrogen content of micron nitrocellulose can reach 12.8%.