Reactive Melt-extrusion Modification Of Wheat Straw And Properties Of Its Composites

Plasticizable biomass materials are made from plants of wood fiber and plastic matrix and a small amount of processing additives after mixing and preparation of new polymer materials by extrusion or pressing prepared.It can be made into sheets,pipe or other shapes according to the needs of both products of plant fiber and plastic,the utility model has the advantages of the waste straw and waste plastic recycling,waterproof,anti corrosion,excellent processing performance,showing large potential application in industry.In this paper,the wheat straw powder was treated with alkalization,then grafted by catalysis M and a specially designed macromolecular emulsion B200 with excellent compatibility with polymer host;FTIR,XRD,scanning electron microscopy and other modern characterization methods have been used to characterize the performance of neat wheat straw and the modified specimens.In addition,a new thermoplastic composite material of wheat straw(named plasticizable wheat-straw materials,PSM)was successfully prepared by twin-screw extrusion in completely under solvent-free conditions.Corresponding conclusions of the study are as follows:(1)Alkali treatment and grafting agent M and B200 on wheat straw powder was successfully pretreated,the hydroxyl group on the surface of wheat straw powder was significantly reduced.Moreover,weakening polarity and compatibility with polymer host was increased;(2)Thermal stabilities of modified wheat straw powder processing is detected to improve to some extent in comparison with that of unmodified samples.DSC curves show apparent glass transition temperature and melting temperature for the modified wheat straw materials,indicating that the surface modification technology can effectively weaken the hydrogen bonds of straw fiber within and between molecules,leading to the flexibility increment of polymer chains;(3)The mechanical properties of the prepared PSM are excellent,the content of B200,M and wheat straw powder had different effects on the specific mechanical properties,and the actual production could be determined according to the specific needs;(4)The modified wheat straw powder has good water resistance,even if the content of modified wheat straw reaches 100wt.%;(5)The modified wheat straw powder has good flame retardancy ability,showing great potential application in the field of home decoration and household products.