Interfacial and mechanical characterisation of biodegradable polymer-flax fibre composites

Replacing glass fibres with flax is a first step in reducing the ecological impact of thermoset composite materials, and employing biodegradable thermoplastic matrix opens up recycling composting as end-of-life routes. Here, range fibre reinforced thermoplastics were investigated: poly-(hydroxy alkanoate) (PHA), poly-(butylene-succinate) (PBS) poly-(lactide) (PLA). Poly-(propylene) (PP) maleic-anhydride grafted poly-(propylene) (MAPP) studied industry benchmarks. This study systematically examines interface between these matrices at multiple scales, explores correlations measured interfacial properties macro-scale properties. Micro-droplet tests reveal that adhesion polymers least similar to flax-MAPP, better than flax-PP. In-plane [±45]s shear tensile on unidirectional composites reaffirm observations micro-scale, polymer/flax present mechanical comparable or MAPP/flax composites. Furthermore, comparison reveals fibre-matrix has substantial role biocomposite performance.