Characterisation of fibre-polymer interactions and transcrystallinity in short keratin fibre-polypropylene composites

摘要

Short fibre reinforced composites were made from keratin fibres obtained from poultry feathers. The matrix material was either polypropylene or a blend of polypropylene and maleic anhydride modified polypropylene (MaPP). In general, the addition of MaPP to polypropylene (PP) did not alter the tensile properties of the blend in a significant way. When not using MaPP, composites had lower breaking stresses than samples without fibres. However, MaPP at concentrations of >4 wt-% enhanced the breaking stress of the composites to above the value without fibres. Concurrent thermal analysis using differential scanning calorimetry (DSC) showed a distinct increase in the amount of transcrystallinity in the composites at MaPP concentrations greater than 4 wt-%. Scanning electron microscopy (SEM) revealed increased interactions between the protein fibres and the PP/MaPP matrix. Annealing showed that more large polymer crystals near the fibres were not enough to increase stress transfer across the interface.