Materials and interface design in semi-structural and eco-friendly wood fiber biocomposites
The project is focused on materials design of biocomposites which are semi-structural, recyclable and/or biodegradable. The term “semi-structural” needs to be defined. If 30wt% glass fiber/polypropylene is selected as the reference material for substitution, it would mean that the modulus should be > 6 GPa and the tensile strength > 85 MPa. In addition, the materials should be recyclable and/or biodegradable. Current wood fiber/polypropylene composites are not biodegradable, and recycling is challenging. The main hypothesis is that multiscale materials and interface design of the composite microstructure can dramatically enhance the performance of wood fiber biocomposites, where high fiber content materials are of particular interest. Materials, interface and process design includes selection and nanoscale design of wood fibers, microscale tailoring of wood fiber organization, new processing concepts, interfaces for improved stress transfer mechanisms, and inorganic/functional additives. Interfaces include both the fiber/polymer matrix interface and fiber-fiber bonds in compressed fibrous materials of little or no polymer matrix phase. In addition, larger scale lamination approaches are explored. Recycling and/or biodegradability are important attributes influencing materials and interface design.
This project is led by Prof. Lars Berglund (KTH) and conducted as a collaboration between KTH, LTU, Chalmers, and Stora Enso.