Preparation And Physicochemical Properties Of Nanocellulose/Polymer Composites

Biomass cellulose is the most abundant natural polymer material in nature.With the shortage of mineral resources and the increasingly serious problems of petroleum base compounds,biological and renewable resources have become the focus of study.Using biomass cellulose as raw material of nano cellulose has the advantages of high mechanical strength,high biological activity and high biodegradability,has good application prospect in various fields.To explore an efficient method for the preparation of bio nano cellulose has become an important way to enhance the utilization of biomass cellulose;and the dispersion of nano cellulose in the polymer matrix has become a factor restricting the development of nano-cellulose in the preparation of nano-composite materials.First,review the research background and present situation of nano cellulose and nanocomposite.The existing preparation methods of nano cellulose and nanocomposite were analyzed.The experiment scheme and experimental framework were presented.Secondly,the analysis of cellulase enzymatic mechanism,and the process parameters are given to the factors that affect the fiber enzyme environment temperature and enzyme concentration setting,and with the use of cellulose pretreatment compared with NaOH/ urea solution,find the best way of enzyme pretreatment program.Thirdly,the effects of different grinding times on the cellulose of the size,structure and crystal of nanocellulose were analyzed by scanning electron microscopy,Fourier transform infrared spectroscopy(FTIR)and XRD.The results showed that the particle size distribution of the nanocellulose prepared by enzymatic pretreatment and 35 mechanical grinding was uniform and the average size distribution was between 0.02-0.05?m.After mechanical grinding,the crystallinity of the nanocellulose changed.The fiber was refined by the enzyme pretreatment and mechanical force,the crystal structure did not change.Finally,the nanocellulose / epoxy resin composites were prepared by miscibility method using the prepared nanocellulose and epoxy resin.The mechanical properties,cross-sectional structure and Fourier transform infrared spectroscopy(FTIR)of the composites were investigated.The results showed that the tensile strength and elastic modulus of the composites increased with the increase of the cellulose content.,The strength of the material reaches the maximum when the content of cellulose is 0.2%.From the Fourier transform infrared spectroscopy,it can be seen that the nanocellulose can be uniformly dispersed in the epoxy resin material.