Study On Preparation And Application Of High Strength Cellulose Paper

With the continuous enhancement of national environmental protection and the gradual awakening of citizens' awareness of environmental protection,many polluting enterprises are facing rectification and bankruptcy.Nowadays,people are more and more pursuing environmental protection and sustainability,and cellulose is a sustainable and eco-friendly material.Cellulose is the most abundant natural polymer on the earth.Cellulose fiber is a kind of cellulose material,which is obtained by further processing natural cellulose(such as various kinds of wood,straw,forage,etc.),which has the advantages of low cost,renewable and biodegradable.Therefore,wood pulp cellulose has been widely used,such as biomedicine,optical materials,lithium battery separator and so on.Based on the research idea of environmental protection and sustainability,this paper studies the preparation of wood pulp cellulose,and mixes it with silver nanowires and graphite nano chips to explore its application in the fields of gas resistance and thermotherapy.The specific research content mainly includes the following three parts:(1): High strength cellulose barrier paper was prepared by chemical free ball milling.It has been reported that high-strength cellulose paper usually needs to use chemicals in the manufacturing process,which is not conducive to sustainable development.In this chapter,the wood pulp paperboard purchased directly is first crushed by a grinder,and then the tough cellulose paper can be prepared by simple ball milling in water without any chemicals.After ball milling for 60 min,the cellulose paper showed a tensile strength of about 90 MPa,accompanied by ductile fracture.More importantly,the oxygen permeability of cellulose paper is very low,two orders of magnitude lower than that of synthetic barrier polymer.Combined with the advantages of low cost and environmental protection,cellulose paper is very competitive as a gas barrier material.(2): The loaded surface of high strength cellulose paper is interlocked with silver nanowires.Using eco-friendly and low-cost high-strength cellulose paper as flexible substrate,Ag NW was loaded on the surface to prepare flexible heater.Ag NWs is partially covered by cellulose and forms a surface interlock structure with substrate without any posttreatment.The results show that the flexible heater works well under the condition of severe mechanical bending and will not lose the electric heating performance.In addition,due to its low resistance,the flexible heater can reach about 80 ? in 10 seconds under 4 V low pressure.Flexible heaters have great potential in heating applications involving curved surfaces such as thermotherapy and defrosting.(3): The preparation of cellulose composite paper by ball milling and its low-pressure flexible electrothermal properties.The composite flexible heater with high conductivity and durability was prepared by blending and milling the eco-friendly cellulose and graphite nanoflakes(GNP)in water.The GNP in the cellulose matrix can reach a high conductivity of 66.5 S / cm at 20 wt%.At the same time,due to the decomposition of the original cellulose microfibers during ball milling,the cellulose composite paper shows excellent mechanical properties.Cellulose composite paper can reach the saturation temperature of 76.8 ? at 5 V low pressure,and can work well without loss of heating efficiency under severe bending.Cellulose composite paper has great potential in the application of low pressure flexible heating.