Sustainable Enhancement of the Mechanical and Flammability Performances of Keratinous Feather-PP Composites: The Effects of Processing Temperature and Solvent Choice

Abstract

This paper discusses two major issues: (i) understanding the influence of the solvent used for fibre processing to obtain flame-retardant chicken feathers, and (ii) establishing the importance of the fibre–matrix blending temperature before composite manufacturing. Three temperature profiles for the extrusion die have been taken into consideration: a low-temperature profile (40 °C) (LT-FRCF), a medium-temperature profile (120 °C) (MT-FRCF), and a high-temperature profile (200 °C) (HT-FRCF). Due to better mixing, the tensile strengths for the medium- and high-temperature profile specimens improved by approximately 44% and 83%, respectively. The cone calorimeter results for the samples with water as the solvent for the feather modification showed a 22% reduction in the peak heat release rate compared to those of the samples with ethanol as the fibre treatment solvent, inferring the importance of the solvent used for the processing and making the process more sustainable with a lower water footprint. The research findings provide clear evidence of how the mixing (extrusion) temperature and choice of solvent for modifying chicken feather fibres affect the composites’ mechanical and flame-retardant properties. These insights contribute to our understanding of how keratinous fibres can effectively serve as flame-retardant reinforcements in polymeric composites.