Effects Of Continuous Steam Explosion On The Mechanical Properties Of Pbs / Vegetable-fiber Composites

Biomass composite, which has advantages of biomass material and polymer materials, has an encouraging prospect for development. It has firstly been investigated internationally from 1960s, and has been developped rapidly in 1980s. Meanwhile, environment protection and sustainable development proposed new requirements on composites' properties, especially on its biodegradability, which has positive significance to material recycling and environment protection. At aspect of polymer matrix, Poly butylene succinate(PBS) has come into polymer research area in 1990s, and has rapidly become research hotspot that can be widely applied as universal-type biodegradable plastics. At aspect of reinforcement, it is a tendency that using cheap straw of short re-growth cycle to replace xylem fiber, however, fiber has quite strong characterastics of polar and hydrophilic, while adhesive substances exist, such as lignin, hemicellulose, pectin substance, which seriously affected its interface compatibility with non-polar hydrophobic matrix, and restricted its application. As a result, modified pretreatment should be done before plant fiber can be used as reinforcement, according to physical or chemical methods. Steam explosion technology is a physical method of plant fiber separation, it has many advantages: high efficiency, low cost, non-pollution, short treatment time, less chemicals, low energy consumption. It is of great benefical to solve interfacial bond issue when using steam explosion technology to modify plant fiber.In this paper, continuous steam explosion equipment has been applied to produce fiber reinforcement in different explosion conditions of cotton stalk skin moisture contents. Then the morphology and structure energy change of cotton stalk bark fiber has been researched, through means of morphology analyzing ,scanning electron microscope(SEM) and TG, and the results come out as how different cotton stalk skin moisture contents influnce fiber explosion pretreatment. Then standard splines have been made,which contain pure PBS and PBS/plant fiber composite.After tensile performance testing, bending performance testing, shock performance testing and SEM analyzing, it draws to a conclusion that how cotton stalk bark fiber moisture content and fiber content influnce composite properties. At last, according to steam explosion equipment, material conveying mechanism, this paper has done some theoretical analysis to various parameters of the steam explosion equipment.The results indicated that: First, with the increasing of cotton skin fiber content,tensile strength of PBS/cotton skin fiber composite firstly decrease, then increase, and at last decrease; mean while, tensile modulus rise straight up approximately; and elongation at break drop down intensely; bending strength and modulus generally increased with cotton stalk bark fiber content increases; while impact strength and energy drop down generally.Second, in order to achieve the best mechanical properties of PBS/cotton skin fiber composite, the best water content of fiber should be 40%, and the best fiber content should be 40%, at this time, the composite's tensile strength reaches to 19.2MPa, bending strength reaches to 22.9MPa, which is 126% more than that of pure PBS, bending modulus reaches to 1211MPa, which is 230% more than that of pure PBS.