Toughening Modification Of Rice Husk/PVC-Based Wood-Plastic Composites

Wood Plastic Composites(WPC)is a wood powder(such as wood flour,straw powder,etc.)and plastic as the main raw material,both to solve the waste plastics caused by "white pollution" problem,but also to improve agriculture and forestry waste Material utilization,turning waste into treasure,is a high value-added industrial products.Wood fiber and plastic without treatment directly according to the ratio of hot pressing,the molten plastic molecules is difficult to wet wood fiber,the material brittle,ductility and impact resistance decreased,and thus made of composite sheet in the physical and mechanical properties difficult to obtain Large increase,especially the impact strength and bending elastic modulus.In order to ensure the selection of high performance wood powder/PVC composites,rice hull,wheat straw and peanut shells were used as raw materials,and three kinds of wood powder and PVC were used as raw materials.The composites were prepared by mixing under stirring at high temperature(160 ℃).The performance of the composites was compared with that of the wood-plastic composites,and the microstructures were analyzed.Shell/PVC-based wood-plastic composite and rice hull added amount of 40wt%.And then the rice husk/PVC-based wood-plastic composites made by adding the rice husk as the follow-up study object.The effects of silane(KH-550)and titanate as the coupling agent on the performance of rice husk and PVC-based wood-plastic composites were studied.The optimum coupling agent-Silane coupling agent(KH-550).Under the modification of silane coupling agent(KH-550),rice husk/PVC-based wood-plastic composites with different wood powder additions were prepared,and the optimum amount of rice hull was 40wt%.By comparing the three different toughening mechanisms,the toughening modification of rice husk/PVC based wood-plastic composites(40wt%of rice husk and KH-550)was explored.In this paper,six different The toughening agents were added to the rice husk/PVC matrix wood-plastic composites according to the same proportion.The mechanical properties,water absorption,thermal properties,infrared spectroscopy,X-ray diffraction pattern and scanning electron microscopy(SEM)of the composites were analyzed by experiments.The following conclusions were drawn:(1)the effect of wood flour on PVC matrix composites.The results showed that the mechanical properties,water absorption,thermal properties and microstructure of the three kinds of woody wood matrix composites were compared with those of rice husk,wheat straw and peanut shell.It was found that when the rice hull was added with 40wt%High hardness,tensile strength and impact strength at the same time bending strength and bending modulus is not low;water absorption is low,better water resistance;thermal conductivity is low,good insulation performance;microstructure and X-ray diffraction The results showed that the degree of adhesion of rice husk and PVC was the most closely.Considering the comprehensive consideration,the addition of rice hull was 40wt%as the matrix of toughening modification experiment.(2)Effect of Coupling Agent on Rice Husk/PVC Matrix Composites.The first part:Select the silane(KH-550)coupling agent and the titanate coupling agent were separately added into the rice husk/PVC-based composite material(rice hull 40wt%),adding 2wt%,by comparing different kinds of The influence of the infrared spectra and mechanical properties of the rice husk/PVC matrix composites after the coupling agent was added.It was found that the addition of the silane(KH-550)coupling agent had higher tensile strength,impact strength,flexural strength and flexural modulus than the titanate many.In addition,the water resistance and heat insulation performance are not greatly improved when they are added,and the water resistance and heat insulation performance of the titanate are poor.Therefore,the silane(KH-550)coupling agent is selected as the rice husk/PVC The best coupling agent for interfacial modification of composite materials.In the ’second part,the silane(KH-550)coupling agent was added into the rice husk/PVC-based composites with different rice hulls,and the mechanical properties,water absorption and thermal properties of the coupling agent were compared and verified.The performance of the composites was the best when the content of rice hull was 40wt%.(3)Effect of short fiber toughening agent on rice husk/PVC based composites.The glass fiber was selected as the toughening agent of the composite material and added to the rice husk/PVC based composite material(40wt%of rice husk and 2wt%for KH-550).The effects of the dosage of the toughening agent on the mechanical properties,water absorption and thermal properties of the composites were investigated.The results were analyzed by infrared spectroscopy and X-ray diffraction analysis.Scanning electron microscopy(SEM)was used to observe the shape and composition of the impact section.It was found that when the addition amount of glass fiber toughening agent was 20wt%,the effect of toughening was the best.(4)Effect of Nano-inorganic Particle Toughener on Rice Husk/PVC-based Composites.The nano-calcium carbonate was chosen as the toughening agent of the composite material,and the rice husk/PVC-based composites(40wt%of rice husk and 2wt%of KH-550)were added.The effects of the dosage of the toughening agent on the mechanical properties,water absorption and thermal properties of the composites were investigated.The results were analyzed by infrared spectroscopy and X-ray diffraction analysis.Scanning electron microscopy(SEM)was used to observe the shape and composition of the impact section.It was found that the synergistic effect of toughening was the best when the addition amount of nano-calcium carbonate toughening agent was 10wt%.(5)Effect of Thermoplastic Elastomer Toughener on Rice Husk/PVC Matrix Composites.The EPDM,POE,EVA and SBS were used as the toughening agent of the composites,and the rice husk/PVC matrix composites(40wt%of rice husk and 2wt%of KH-550)were added.The effects of the dosage of the toughening agent on the mechanical properties,water absorption and thermal properties of the composites were investigated.The results were analyzed by infrared spectroscopy and X-ray diffraction analysis.Scanning electron microscopy(SEM)was used to observe the shape and composition of the impact section.It was found that when the addition amount of EPDM toughening agent was 10wt%,the toughening effect was the best.When the addition amount of POE toughener was 10wt%,the toughening effect was the best.When the amount of EVA toughener was 30wt%,The best effect of toughening is the best.When the addition amount of SBS toughening agent is 10wt%,the toughening effect is the best,and the EVA as the thermoplastic elastomer toughening agent is 30wt%The toughening effect of rice husk/PVC matrix composites is the best.