摘要
以微晶纤维素(microcrystalline cellulose,MCC)为原料,利用离子液体预处理/硫酸水解协同制备纳米纤维素,通过Zeta电位分析、原子力显微镜(atomic force microscope,AFM)、红外光谱、X-射线衍射(X-ray diffraction,XRD)和热分析探究不同质量分数的硫酸溶液(10%~40%)对纳米纤维素结构的影响,并对其稳定Pickering乳液性能进行初步研究。结果表明,经过离子液体预处理后,随着硫酸溶液质量分数增加(10%~40%),纳米纤维素得率逐渐下降,但Zeta电位绝对值逐渐增加;AFM结果表明纳米纤维素形态从长纤丝状网络结构逐渐变为短棒状结构,其长度逐渐减小但直径增加。XRD结果表明纳米纤维素同时具有纤维素I型和Ⅱ型晶体结构,结晶度降低。MCC制备纳米纤维素过程中,经离子液体预处理后氢键结构遭到破坏,热稳定性随着硫酸溶液质量分数的增加也逐渐降低。经不同质量分数硫酸溶液水解制备的纳米纤维素在不同颗粒质量浓度(1~5 g/L)和油相比例(30%~70%,体积分数)下均能稳定Pickering乳液,但40%硫酸溶液制备的纳米纤维素具有更好的稳定Pickering乳液性能。
The nanocellulose was prepared by ionic liquid pretreatment/H_(2)SO_(4) hydrolysis synergistic method using microcrystalline cellulose(MCC)as a raw material.The influence of H_(2)SO_(4) concentrations(10%-40%,on mass basis)on the structure of nanocellulose was studied through analysis of Zeta potential,atomic force microscopy(AFM),Fourier transform infrared spectroscopy,X-ray diffraction(XRD)and thermal gravimetric analysis.The preliminary application of nanocellulose in Pickering emulsion was also evaluated.The results showed after ionic liquid pretreatment,the yield of nanocellulose gradually decreased,but the absolute value of Zeta potential of nanocellulose increased as H_(2)SO_(4) concentration increased from 10%to 40%.AFM results showed that the morphology of nanocellulose changed from long-filament network structure to short rod-like structure,which showing a decrease of length but an increase of diameter.XRD results showed that all the nanocelluloses had both cellulose type I and type II crystal structures with a reduction of crystallinity.The hydrogen bonds structure of MCC was destroyed during ionic liquid pretreatment,and the thermal stability gradually decreased with the increase of H_(2)SO_(4) concentration.All the nanocelluloses can stabilize Pickering emulsion at different particle concentration(1-5 g/L)and oil ratio(30%-70%,on volume basis),but the nanocellulose prepared at 40%sulfuric acid concentration showed a better stable emulsion performance.
作者
张书敏
刘玥
刘洪龙
张宇昊
陈媛
余永
戴宏杰
ZHANG Shumin;LIU Yue;LIU Honglong;ZHANG Yuhao;CHEN Yuan;YU Yong;DAI Hongjie(College of Food Science,Southwest University,Chongqing 400715,China;National Demonstration Center for Experimental Food Science and Technology Education(Southwest University),Chongqing 400715,China)
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2022年第13期148-154,共7页
Food and Fermentation Industries
基金
国家级大学生创新创业训练计划项目(202110635059)
国家自然科学基金项目(31901683)
重庆市自然科学基金面上项目(cstc2020jcyj-msxm1875)
重庆市雏鹰计划项目(CY210202)。
