Development Of Bast Fiber Automotive Interior Materials By Airlaid Technology

In recent years, automotive interior materials are gradually to green environment friendly and low-carbon direction. The traditional materials of automotive interior mainly is GE plastics (PP,PU,PVC,ABS)and the composite material of glass fiber, which can’t regenerate and degradation, especially they have a serious environmental pollution. China has a rich resource of hemp, the strength and modulus of natural hemp are relative higher, which posses anti-bacterial and biodegradation function,so it can be used for the development of automotive interior materials.In this paper,through combining the characteristics of the kenaf fibers with the air laying technology, then submit a new plan for developing the automotive interior materials, that is through use of the natural hemp fibers and hot-melt polypropylene fiber (PP)mixed,to develop an environmentally friendly hemp fiber automotive interior materials.therefore improving the physical and mechanical properties of the product, it also broaden the range of applications of hemp fiber in the field of automotive interior materials.According to the structural characteristics of aerodynamic web. designing the production process of Kenaf/PP automotive interior liner, and studying the relevant process parameters, adopting single-factor test method to study the blend ratio of Kenaf and polypropylene fibers、the speed of wind turbine under aerodynamic web machine、the speed of transportation curtain of aerodynamic web machine、the rotational speed of cylinder during the process of forming a network, analyzing how it influences bending strength、tensile strength、impact strength of Kenaf/polypropylene fiber composite automotive interior plate. Through orthogonal test analysis, obtaining optimum process parameters:the blend ratio of Kenaf/PP is30/70,the speed of fan is950r/min, the speed of transportation curtain is2.5m/min, the rotational speed of cylinder is700r/min.In order to improve the uniformity of the fiber sheet, this paper made a creative design to duct by the principle of aerodynamic, and took two-dimensional modeling and meshing grids for air duct based on Gambit, where the boundary type and medium type were defined. Meanwhile, imported model into Fluent finite element analysis software. Based on k-ε standard turbulence model duct internal flow field, simulation and numerical analysis are made. Through the analysis of the internal pressure and cloud wind velocity vector chart, the wind zone on the top was in the high-pressure, and the low pressure area was for left, at this time, gas began to flow under the influence of the pressure difference. Gas speed is the fastest in the entrance into nets duct, and the slowest at the exit, then differential pressure also is the largest. It indicates that the design of the various parameters duct are reasonable, and that adopting the asymptotic expansion of structure venturi pipes with the spread of the airflow law is beneficial to the fiber evenly and mixed, and to improve fiber into nets of evenness.