Sustainable Sandwich Composites Manufactured from Recycled Carbon Fibers, Flax Fibers/PP Skins, and Recycled PET Core

High versatility of polyethylene terephthalate (PET) waste for the development of batteries, biosensing and gas sensing devices

Continuously growing adoption of electronic devices in energy storage, human health and environmental monitoring systems increases demand for cost-effective, lightweight, comfortable, and highly efficient functional structures. In this regard, the recycling and reuse of polyethylene terephthalate (PET) waste in the aforementioned fields due to its excellent mechanical properties and chemical resistance is an effective solution to reduce plastic waste. Herein, we review recent advances in synthesis procedures and research studies on the integration of PET into energy storage (Li-ion batteries) and the detection of gaseous and biological species. The operating principles of such systems are described and the role of recycled PET for various types of architectures is discussed. Modifying the composition, crystallinity, surface porosity, and polar surface functional groups of PET are important factors for tuning its features as the active or substrate material in biological and gas sensors. The findings indicate that conceptually new pathways to the study are opened up for the effective application of recycled PET in the design of Li-ion batteries, as well as biochemical and catalytic detection systems. The current challenges in these fields are also presented with perspectives on the opportunities that may enable a circular economy in PET use.

Development of epoxy-based sandwich composite panel with hollow glass microspheres/clay hybrid core and banana fiber facesheet for structural applications

This study focuses on improving the mechanical properties of sandwich composites by developing epoxy-based sandwich composite panels with hollow glass microspheres/nanoclay hybrid core and banana fiber facesheets for structural applications. The mechanical performance of sandwich composite panels made with hollow glass microspheres (HGM)/nanoclay hybrid core with banana fibers face-sheet composites panel is investigated in this work. The HGM content of the core was varied from 1 wt% to 3 wt% in the sandwich composites panel, while the nanoclay content of the core was varied from 1 wt% to 5 wt% in each of the HGM-filled series of the sandwich composite panel, these sandwich composite panels were fabricated using a conventional resin casting method. In this investigation, the mechanical, water absorption, and buoyancy behavior are thoroughly studied and the findings revealed better improvement at the sandwich composites with hybrid core formulation with banana fiber facesheets than the sandwich composites without hybrid core formulation. This demonstrates that banana fiber with epoxy resin has a limited amount of strength when used without a hybrid core but delivers better performance when HGM and clay particles are mixed as the hybrid core because of excellent interfacial adhesion between the hybrid core and the matrix. The improved mechanical properties could suggest that this material may be suitable for application in industries where sandwich structures that are lightweight with good mechanical properties are required. This study showed a new area of sandwich structure development by enhancing mechanical properties using hybrid core and banana fibers.