In response to increasing environmental concerns, significant efforts have been made to reduce our reliance on fossil fuel-based plastics, driving the development of sustainable alternatives such as polyhydroxyalkanoates (PHAs). This study investigates the processing of various PHAs into fibres, focusing on their morphological, thermal, and mechanical properties. Different PHAs were spun into fibres at a 15% (w/v) concentration using wet-spinning techniques. Among the PHAs studied, commercially available PHBHHx, used as a reference, exhibited spongy morphology in the fibres and demonstrated thermal vulnerability due to its rapid degradation. Blended fibres showed enhanced morphological and mechanical properties compared with neat fibres. In Fourier-transform infrared spectroscopy (FTIR), no differences were observed between the unprocessed polymers and the wet-spun polymeric fibres, indicating that the wet-spinning process did not affect the molecular structure of the polymers. Thermal and mechanical evaluations confirmed the miscibility between the polymers in the blends. Overall, these results highlight, for the first time, the successful production of wet-spun fibres from two modified P(3HB) variants, individually, in combination with each other, and in blends with the well-established commercial PHA, PHBHHx. However, this study also underscores the need to optimise feed rates to enhance fibre production efficiency and mechanical strength, thereby broadening their potential for various applications.

In response to the increasing environmental concerns, significant efforts have been made to reduce the reliance on fossil fuel-based plastics, driving the development of sustainable alternatives such as polyhydroxyalkanoates (PHAs). This study investigates the processing of various PHAs into fibres, focusing on their morphological, thermal, and mechanical properties. Different PHAs were spun into fibres at a 15% (w/v) con-centration using wet spinning techniques. Among the PHAs studied, commercially available PHBHHx, used as a reference, exhibited a spongy morphology in the fibres and demonstrated thermal vulnerability due to its rapid degradation. Blended fibres showed enhanced morphological and mechanical properties compared to neat fibres. In Fouri-er-transform infrared spectroscopy (FTIR), no differences were observed between the unprocessed polymers and the wet spun polymeric fibres, indicating that the wet spinning process did not affect the molecular structure of the polymers. Thermal and mechanical evaluations confirmed the miscibility between the polymers in the blends. Overall, these results highlight the potential of polymer blending to enhance fibre functionality and broaden their application potential. However, the study also empha-sizes the need to explore optimized feed rates to improve fibre production efficiency and increase their resistance, to enlarge their suitability for various applications.