【摘要】 采用稀酸预处理纤维素浆粕,结合高压均质的物理方法,制备出一维棒状纳米纤维素。通过傅里叶红外光谱(FTIR),X射线衍射(XRD),热重分析(TGA),原子力显微镜(AFM)和透射电镜(TEM)等方法对纳米纤维素光谱性能和形貌结构进行了表征。结果表明,制得的纳米纤维素与纤维素浆粕具有相同的红外特征官能团,但分子内氢键缔合作用被部分破坏。纳米纤维素与纤维素浆粕同属于纤维素Ⅰ的晶形类型,结晶度从59%提高至70%,仍保持结晶区与无定形区共存的状态。纳米纤维素的分解温度为330℃,热稳定性低于纤维素浆粕,失重温度从292℃持续至500℃,有两个明显失重阶段。纳米纤维素长度为数百纳米,宽度为数十纳米的棒状形态,易产生团聚现象。更多还原

【Abstract】 The object of the present paper was researching a kind of nano cellulose prepared by the pretreatment of diluted acid and the physical method of high pressure homogenization.The cellulose pulp was pretreated by diluted acid and then prepared by high pressure homogenization.The one-dimensional rodlike nano cellulose was obtained.And the spectral properties of nano cellulose were characterized by Fourier transform infrared spectroscopy(FTIR) and X-ray diffraction(XRD).The thermal property of nano cellulose was analyzed by thermogravimetric analysis(TGA).The dimension and morphology of nano celluose were observed using atomic force microscope(AFM) and transmission electron microscopy(TEM).FTIR analysis results showed that the one-dimensional rodlike nano cellulose had the same characteristic functional groups as cellulose pulp.And it was showed that intramolecular hydrogen bond association effects of nano cellulose were partly destroyed.It was indicated by XRD analysis that nano cellulose and cellulose pulp corresponded to the crystal type of cellulose Ⅰ.The crystallinity of nano cellulose was increased from 59% to 70%,compared to cellulose pulp.Nano cellulose still maintained both crystalline domains and amorphous regions,although crystalline domains and amorphous regions were partly damaged by preparing process.Thermal analysis results demonstrated that the thermal stability of nano cellulose was lower than that of cellulose pulp.The decomposition temperature of nano cellulose was 330 ℃.Two weight-loss stages were present in the range 292～500 ℃.The TEM photograph showed that nano cellulose was significantly rodlike shape with hundreds of nanometer in length and tens of nanometers in width.AFM image showed that nano cellulose was agglomerated together.更多还原