内切纤维素酶协助TEMPO氧化制备纳米纤维  

Endo-glucanase Assisted Preparation of TEMPO Oxidized Cellulose Nanofibers

作　　者：赵海儒 吴淑芳[1] 宋君龙[1] 丁少军[1] 

机构地区：[1]南京林业大学江苏省制浆造纸科学与技术重点实验室,江苏南京210037

出　　处：《纤维素科学与技术》2015年第4期55-61,共7页Journal of Cellulose Science and Technology

基　　金：国家自然科学基金项目(31470593)

摘　　要：利用内切型纤维素酶(EG1)预处理全漂硫酸盐针叶浆,再经过超声波协助2,2,6,6-四甲基哌啶氧自由基(TEMPO,2,2,6,6-tetramethylpiperidine-1-oxyl radical)氧化制备纳米纤维。通过氧化还原滴定和电导滴定监测TEMPO氧化过程中残余有效氯和纤维中的羧基含量的变化,并利用纤维粒度分析仪、毛细管粘度计和透射电镜分析制备纤维样品的尺寸分布、流动性能以及纤维形貌,研究了EG1预处理对超声波协同TEMPO氧化制备纳米纤维的影响。结果表明:相同的TEMPO氧化条件下,经10 U/g EG1预处理12 h、24 h和48 h后,纤维羧基含量分别由2.05 mmol/g增加到2.35 mmol/g、3.03 mmol/g和3.13 mmol/g;与对照相比,经EG1预处理再TEMPO氧化制备的样品透明度增加,纤维尺寸减小,流动性下降。Bleached softwood pulp was pretreated by EG1, then cellulose nanofiber （CNF） was prepared by a 2,2,6,6-tetramethylpiperidine-l-oxyl radical （TEMPO） oxidation with ultrasonic. The residual active chlorine of cellulose/water slurry or dispersions and carboxyl group content of fiber could be monitored by redox and conductivity titration during TEMPO oxidation process. The particle size distribution, viscosity of dispersions and fiber morphology of nanofibers could be characterized by nanoparticle size analyzer, capillary viscometer and transmission electron microscopy （TEM）respectively. The results indicated that under the same conditions of TEMPO oxidation, carboxyl group content of cellulose was improved to 2.35 mmol/g, 3.03 mmol/g and 3.13 mmol/g from 2.05 mmol/g at 12 h, 24 h and 48 h respectively. Comparison with control sample, viscosity and transparency of nanofibers was increased, fiber size distribution was more uniform.

关 键 词：内切纤维素酶 纳米纤维 TEMPO氧化 漂白针叶浆 

分 类 号：TQ316.322[化学工程—高聚物工业]