Study On The Preparation And Properties Of Cork/Bamboo Composite

Cork is a part of the bark peeled from cork oak Quercus variabilis,it has a low density,good elasticity,heat and sound insulation properties,which is an excellent natural renewable rare resource.At present,the composite material prepared mainly by cork granules,combined with fibers,high molecular polymers,non-metals,etc.,is one of the most promising fields in the industrial productin and application of cork.The study of cork-based composite materials is of great significance for exerting the advantages of cork material and enriching the types of cork products.Bamboo has the characteristics of fast growth and good flexibility,and its tensile strength is about twice that of cultivated wood in plantations,so it can be used as a potential composite component.The research of cork-based composite materials is of great significance for improving the defects of poor mechanical properties of cork materials,and saving cork resources.In this study,cork granules(CG)、Neosinaocalamus affinins and polyurethane adhesive(PU)were used as raw materials to prepare cork/bamboo composite(CBC)by hotpressing process.The factors affecting the physical and mechanical properties of CBC and preparation process optimization were systematically studied,SEM,UDM and FTIR were used to analyze the strengthening mechanism of bamboo,which provided scientific basis and technical support for the application of cork-based composites.Through the researches above,the main conclusions were as follow:1.The optimal preparation process of CBC was determined as: hot pressing time of 6 min,hot pressing temperature at 160°C,resin content at 6 wt%,and bamboo particles content of 10wt%.For such CBC,the tensile strength,WSR,WAR and TSR were 2.246 MPa,0.93%,9.64%and 23.66%,respectively.2.The physical and mechanical of CBC were controllable.Different performance levels of CBC can be fabricated by adjusting hot pressing time,hot pressing temperature,resin content and bamboo particles content according to meet the requirements of the water resistance and mechanical properties of CBC.Hot pressing time had an extremely significant effect on the TSR of CBC,the resin and bamboo particles content had a significant impact on the WAR;the resin content had a significant effect on WSR,the resin and bamboo particles content had a significant effect on the WSR.The optimum process of CBC was determined as: hot pressing time of 6 min,hot pressing temperature at 160°C,resin content at 6 wt%,and bamboo particles content of 10wt%.For such CBC,the tensile strength,WSR,WAR and TSR were 2.463 MPa,0.76%,4.93%and 17.19%,respectively.3.The hot-pressing time and resin content have a significant effect on the physical and mechanical properties of CBC.The water resistance of CBC gradually increased as the hotpressing time increased,the tensile strength increases as the hot-pressing time increases from 3min to 5 min,beyond which the tensile strength of CBC decreased slightly;The water resistance and tensile strength of CBC gradually increased with the increasing of resin content.Besides,when the resin content was increased from 5 wt% to 6 wt%,there was no significant difference in water resistance and tensile strength of CBC.4.Density has a significant effect on the physical and mechanical properties of CBC.The TSR and WAR of CBC gradually increased as the density increased,and the tensile strength gradually increased as the density increased from 0.4 g/cm3 to 0.7 g/cm3.When the density increased from 0.5 g/cm3 to 0.6 g/cm3,there was no significant difference in the TSR,WAR and tensile strength of CBC;it continued to increase to 0.7 g/cm3,the tensile strength of CBC increased significantly.Compared with other cork-based composite materials,CBC has outstanding mechanical properties and has considerable potential for application in fields such as cork flooring and interior decoration.5.The bamboo particles form effective "bridging" structure between the cork granules and the adhesive,which enhances the bonding interface strength of CBC;the porosity of CBC,the degree of cork cell deformation are negatively correlated to its density.Most of the pores of the low-density CBC are concentrated in the lager pore area,end the pores of the high-density CBC are relatively small.