纳米纤维素晶体的制备及表征

Preparation and Characterization of Nanocrystal Cellulose

采用超声波辅助硫酸水解、高速离心取其上清层水溶胶的方法由微晶纤维素(MCC)制备纳米纤维素晶体(NCC),并采用场发射透射电子显微镜(FETEM)、场发射环境扫描电子显微镜(FEGE-SEM)、X射线衍射仪(XRD)和傅里叶变换红外光谱仪(FTIR)对所制备NCC的尺寸与形态、结构、组成和光谱性质进行分析。结果表明:FETEM和FEGE-SEM观察所制备纳米纤维素晶体形态相同,呈棒状,直径和长度主要分布在2～24nm和50～450nm;XRD图谱表明NCC仍属于纤维素Ⅰ型,结晶度为77.29%,晶粒尺寸为3～6nm;FTIR分析表明所制备的纳米纤维素晶体仍然具有纤维素的基本化学结构。

Nanocrystal cellulose（NCC） was prepared from microcrystalline cellulose（MCC） by sulfuric acid hydrolysis assisted with ultrasound,in addition the NCC was obtained from supernatant hydrosol of high-speed centrifugation.Furthermore,the size and morphology,crystal structure and spectral properties of NCC were investigated and analyzed with field emission transmission electron microscopy（FETEM）,field emission gun environment scanning electron microscopes（FEGE-SEM）,X ray diffraction（XRD） and Fourier transformation infrared spectroscopy（FTIR）.The results show that the same like morphology of NCC can be observed by FETEM and FEGE-SEM,they are rod like,and the diameter is about 2-24 nm,with the length of 50-450 nm.Moreover,the XRD pattern show the NCC is characteristic of the celluloseⅠcrystal form,and the crystallinity of NCC is 77.29%,the grain size is about 3~6 nm.On the other hand,NCC still keep with the basic chemical structure of cellulose analyzed with FTIR.