Preparation And Properties Of The Noil Ramie Fibre Reinforced High Density Polyethylene Composites

Composite reinforced with natural fiber can have the same mechanicalproperties as those reinforced with glass fiber, and it has many advantages, forexample, simple process, low cost and less energy consumption. Importantly,natural fiber reinforced composites are an environment-friendly material,which meets the requirements of environmental protection. Compared to thelong hemp fibers, noil fibers have the same strength and modulus ratio.However, noil fibers especially in foreign countries are usually discarded aswaste.In this paper, ramie noil fiber was used as reinforcement to strengthenhigh density polyethylene resin matrix. Considering the disadvantage of noilfibre, banbury mixer and changing short fibre to continuous fibre were used inprocessing. In this paper we focused on the several important factors, forexample, fiber content, fiber dispersion and interface between fiber and resinmatrix.Result obtained by mechanical properties test indicated that the tensileproperties, bending properties and the thermal stability of composite were effectively improved by natural fibre, when increased the fiber content in the0-20%range of the mass fraction. Comparing two different compatibilizers, itwas found that MAH-g-PP is important for the role of reinforcement, andwhen MAH-g-PP is5wt%or10wt%, the composites have good mechanicalproperties. In addition, the result of scanning electron microscope (SEM)indicated that the compatibilizer was helpful for the resin matrix to wrap upthe fiber. MAH-g-PP also improved the thermal stability and crystallinity ofthe composites. By dynamic mechanical testing and using of interface strengthcoefficient B, it could be further found that interfacial adhesion between fiberand matrix resin was improved by MAH-g-PP.Exploring the fiber-reinforcing mechanism, the FTIR results showed thatthe presence of ester linkage at the interface reduced the hydrophily of fiber toenhance the compatibility. By introducing micro-mechanical model, it wasfound that fiber could help bearing stress.The affect of one time granulation or twice granulations on mechanicalproperties of the composite was studied. The affects of screw rotation speedand temperature on the mechanical properties of composites were alsoreseached in this paper.In addition, the effects of AC forming agent on the density andmechanical properties of composite and the continuous ramie noil reinforcedcomposites were also studied.