Study On Characterization And Application Of Tea-plastic Composite

In recent years, the industry of wood plastic composites (WPC) is expanding well and fast with technological advances and the increasing of environmental awareness.The rapid development of WPC industry has alleviated some environmental issues such as excessive deforestation, ecological deterioration, plastic pollution. Tea stems and other tea residue are rich in natural plant fiber, which is good resource of raw material for WPC. It is not only an innovative on the study of WPC made from tea-plastic composite, but also a actively exploration to the resource utilization of tea residues, which is significant to both WPC and tea industry.In this paper, tea residue and high-density polyethylene as the main raw material, the properities of tea stem fiber, such as morphology and chemical component groups, were examined clearly by using physical as well as chemical methods. The mechanical properties, water resistance, rheological properties, thermal stability and microstructure of tea plastic composites were characterized and analyzed through the test of mechanical properties and water absorption, thermal gravimetric, scanning electron microscope analysis and so on, so as to obtain good ratio of each components, comfortable optimal process and technical parameters. And on this basis the application study of tea-plastic products were conducted. The main conclusions of were as follows:(1)The contents of cellulose, hemicellulose and lignin of tea stems were 9.4%, 31% and 9.7% respectively. The content of cellulose and lignin were lower significantly than that of wood, but the content of hemicellulose was nearly the same. The initial thermal decomposition temperature of tea stem fiber was around 205 ?, with a maximum weight-loss rate around 339.2 ?. The analysis of scaning electricity microscope showed that some tea stems fibers existed as fiber bundles, some spread out, the appearance of tea stems observed as class rectangle or rod-shaped integrally.(2) The mechanical properties and water resistance of composite could achieve optimal effect when the particle content of tea stems was 30%, with a size of 100 mesh,and 8% of coupling agent.(3) There was significant difference in thermal stability between 30% tea-addative and non-addative composite; while the therml stability of 100-mesh compostite was higher than that of 20-mesh, and adding 8% MAPE could significantly improve the thermal stability compared with 1.8% KH-550.(4) The analysis of microstructure of tea-plastic composite showed that the combination of the tea stems particle with substrate HDPE could achieve optimum effect with 30% tea stems particle and a particle size of 100 mesh; the addition of 8% MAPE and 1.8% KH-550 could improve the interface compatibility and dispersion of composites compared with that of non coupling agent, the effect was better with 8% MAPE.(5) In applied research aspect of tea-plastic composite,the optimum formula parameters were as follow:30% tea stem,with 100 mesh particle size, and 8% MAPE coupling agent; determine the production process of composite;and the technology parameters were as follow:90 ?mixing temperature,300 r · min-1 rotating speed,15 min blending; the temperature set three sections of granulation auxiliary should be 175,170 and165 ? respectively, with 40 r · min-1 rotating speed, the temperature setting of nozzle, screw section one and two of injection molding machine should be 175,170 and 165 ? respectively, holding for30 s.