Grant: Discovery Grants Program - Individual

Short-fiber composites (SFC) rely on the exceptional properties of the reinforcing fiber phase to enhance the properties of the matrix. Depending on the product application required, the fibers must be arranged in a particular orientation, either in-plane, through-plane, etc. Due to cost and mass-production concerns, through-plane fiber orientation is usually not pursued. This proposal seeks to develop composites with through-plane aligned (TPA) fibers, as they can significantly improve properties of SFCs for use in a number of existing applications. Moreover, many new and innovative applications can be envisaged if through-plane alignment of fibers can be properly controlled. The most common way of controlling the in-plane alignments is by applying a shear flow field, which can be inherently generated in extrusion or injection molding processes. Aligning fibers perpendicular to the plane (through-plane) is more difficult because of the challenges in controlling the shear flow field. Many techniques are based on utilizing electromagnetic forces on particles in fluid suspensions and then solidification. Mechanical methods are not suitable for large scale production. Possible applications include electrically and thermally conductive coatings, wear resistant surfaces, permeable membranes, heat sinks, and innovative sensors etc.*Therefore, the objective of this research program is to develop innovative manufacturing techniques for high throughput production of TPA SFCs, which are more suited for certain applications than random SFCs. Success in doing so will have a dramatic effect in opening up a number of applications which are not even being considered at present for SFCs. *Two distinct methodologies will be investigated for through plane alignment of fibers. A) Foaming in SFC thin sheets, where the bubbles in matrix are forced to undergo biaxial stretching, rupture and form open pores which will align large number of fibers laterally. B) Extrusion followed by post-processing folding and curing. This research proposes to first align the fibers in the planer direction using extrusion and followed by folding like operations and curing to improve the surface to surface bonding of the folded layers. Both the methods require extensive design and development efforts and application of innovative approaches to solve design challenges. The initial phase will focus on the first methodology proposed above.*Work on through-plane fiber alignment is sparse and achieving technology for high throughput through plane alignment in SFCs has the potential to dramatically increase the usefulness of composite materials and generate many novel and innovative applications, which will be beneficial for the plastics manufacturing industry of Canada. It will also be a source of training and innovation experience for HQP in this industry.