CAJ | 학술논문

文中对水解制备得到的纳米微晶纤维素采用了两种不同的处理方法以提高其热稳定性:于60℃下反复加热洗涤以减少其硫酸氢根含量或加入NaOH中和表面的硫酸氢根.研究表明:这两种方法都可以有效提高纳米微晶纤维素的热稳定性.与普通纤维素在热降解过程中只形成一个主要裂解区间不同,所有纳米微晶纤维素样品不仅存在主要裂解区间,而且在高温区域(＞400℃)还存在一个明显的第二裂解区间.同时所有纳米微晶纤维素样品最终生成的焦炭产量很相近(3.5%～5.0%).这说明当纤维素颗粒的粒径小至纳米尺寸时,外部催化剂的存在只是改变了其热降解的途径,但其整体热降解行为和最终的焦炭产量受其纳米颗粒特性所主导.文中还利用分峰拟合的方法表明在纳米微晶纤维素的主要裂解区间存在两个平行的竞争反应.
문중대수해제비득도적납미미정섬유소채용료량충불동적처리방법이제고기열은정성:우60℃하반복가열세조이감소기류산경근함량혹가입NaOH중화표면적류산경근.연구표명:저량충방법도가이유효제고납미미정섬유소적열은정성.여보통섬유소재열강해과정중지형성일개주요렬해구간불동,소유납미미정섬유소양품불부존재주요렬해구간,이차재고온구역(＞400℃)환존재일개명현적제이렬해구간.동시소유납미미정섬유소양품최종생성적초탄산량흔상근(3.5%～5.0%).저설명당섬유소과립적립경소지납미척촌시,외부최화제적존재지시개변료기열강해적도경,단기정체열강해행위화최종적초탄산량수기납미과립특성소주도.문중환이용분봉의합적방법표명재납미미정섬유소적주요렬해구간존재량개평행적경쟁반응.
In order to improve the thermal stability of the cellulose whiskers obtained by the hydrolysis with sulfuric acid, two methods were adopted to treat the cellulose whiskers. One is the repeated desulfation with heating at 60℃ to reduce the hydrosulfate content, and the other is the neutralization with NaOH solution to neutralize the hydrosulfate on the surface. The results indicate that both the two methods can effectively improve the thermal stability of cellulose whiskers. As compared with microcrystalline cellulose, cellulose whiskers have a second pyrolysis stage at high temperature ( more than 400℃ ) except the primary pyrolysis stage, and the final char yields are very similar in amount (3.5% ～ 5.0% ). All these above-mentioned findings show that, for cellulose whiskers, the presence of external catalyst can only change the thermal decomposition pathway, and that the thermal pyrolysis and the final char yield are determined by the characteristics of the nano-sized particles. Moreover, the profile analysis of thermo gravimetric derivative curves shows that there are two remarkably competitive reactions in the primary pyrolysis stage of cellulose whiskers.