Seminars and thesis defenses
Thick glass fiber reinforced thermoplastic methacrylic composites : properties & optimization
By Sarah Gayot (iMMC / IMAP)
As part of the energy transition, the recycling goals applicable to end-of-life materials are getting more and more demanding. Thanks to a recyclable matrix, continuous fiber reinforced thermoplastic composites have attracted growing interest over the past twenty years for the design of lightweight and high-performance structural parts. To produce such materials, specific monomers are usually vacuum-infused through glass or carbon fibers before undergoing in-situ polymerization. Though most composite parts obtained this way are only a few millimeters thick, certain applications require the manufacturing of much thicker components – up to several centimeters –, which can give rise to defects in the final part. In particular, porosities can form at several scales, and their influence on the mechanical behavior of the part must be controlled and understood. In this perspective, the present study focuses on the links between the infusion conditions, the physico-chemical state and the mechanical properties of 7-cm-thick glass fibre reinforced thermoplastic methacrylic composite plates, at both the micro- and macroscopic scales. Current results suggest that, while the in situ micromechanical properties of the methacrylic matrix barely vary with the infusion temperature, it strongly affects the amount and distribution of porosity in the composite part – which, in turn, governs the macroscopic mechanical properties of the final composite part and their variability.