Study On Bamboo Fiber/PP Composite For Automobile Inner Parts

In recent years,natural fiber composite materials have caught widespread attention by the global automobile industry;many countries compete to develop new green recyclable biodegradable materials for automobile manufacturing.Bamboo fiber as a kind of high performance natural fiber material has much superiority that other fiber materials do not match,such as extensive sources,low cost,renewable,heat and acoustic insulation.But the bamboo fiber composite material has not been systematic deep research due to technical problems to prepare bamboo fiber in the past years.And compared with glass fiber and its composite materials,the bamboo fiber composite still has the problem of high water absorption and lack of bending properties in the automobile materials,and the problems have not been solved effectively.Due to the limited experimental conditions on the preparation of automotive interior materials in China,writer did the experiment in Doshisha University machinery specializing laboratory in Japan which has cooperation with TOYOTA and NISSAN.In view of the current problems in the automotive inerior materials,bamboo fiber composites should be explored more without changing the nature of bamboo fiber and preparated high performance and low cost materials.This article depends on the bamboo fiber preparation,composite interface modification,composite preparation process and the matrix modification,and launches a series of related research.The main research methods and achievements are as follows:A.For the high water absorption of the bamboo fiber composite,the water absorption properties of bamboo fiber is examined.Found that the longer bamboo fiber(more than 20mm)is weak than fluffy or powdery bamboo fiber(less than 15mm).The long bamboo fiber has been designed to preparat a set of different aspect ratio,the length is in the range of 20~130mm,the average aspect ratio is in the range of 483~713.B.Taking into account the properties of bamboo fiber and PP fiber,the non-fabric and hot-pressing technology is designed as composite process.This technology can uniformly mix fibers(length between 2~15cm)and build them into 3D networks for achieving efficient crosslinking structure.Considering the density of automotive interior materials is 0.5g/cm~3,the non-fabric mat layer is set at 0.12g/cm~2,cutting size for each mat is 150?120mm;due to the absorption of bamboo fiber,the quality is 28.3~28.5g/mat;the hot pressing parameter of bamboo fiber composite is 5MPa for 1min at 220~0C.C.In order to obtain the bamboo fiber composites with high performance and low water absorption curve,matrix PP fiber selected is added about 5%wt of maleic anhydride grafted polypropylene fiber(MAPP),experiments show that the bending properties of the composite increased 45%,water absorption decreases 60%;50~60%wt bamboo fiber content can obtain the excellent bending performance in the composite;as well as the aspect ratio of bamboo fiber between600~700.The best bending strength,bending modulus,specific strength and specific modulus are54.72MPa,3.79GPa,87.59N·m/g,6.06KN·m/g,respectively.Comparing the Halpin-Tsai prediction model with the bending modulus of the composite material,found that anisotropy factor is effective to modify the model by Thomason and other scholars which makes the prediction of Halpin-Tsai equation more close to the experimental results,the similarity is about 88%.D.To strengthen the 3D structure of the BF/MAPP composite mat,PVA pretreatment is used to immerse the mat for 1min.This process can make the fiber between crosslinking points are precuring.3%wt PVA solution can obtain higher mechanical properties of composite;comparison with untreated composite,PVA can substantially improve 12%of the bending modulus of BF/MAPP compositest.E.The industrialization development of bamboo fiber composites is on its way.Considering the oiling process for industrial preparation natural fibers,the lubricate remains on the bamboo fiber,which will affect the interface between composite materials,and it should be removed.Thus,the acetone process is proposed in this paper,and the experiment result shows that acetone cleaning increases about 17%and 9%on the bending strength and bending modulus.