Stabilisation of sheep wool fibres under air atmosphere: Study of physicochemical changes

Natural fibres constitute interesting, low cost and environmentally friendly precursors of carbon fibres. However, they are prone to fuse degrade upon thermal treatment, affecting the properties products unless a stabilization step was included. Aiming reach better understanding mechanism wool as potential precursor for preparation fibres, in this study we have analysed chemical, structural morphological transformations during its oxidative air. Below 400 °C, both structure morphology were preserved. The chemical composition changed with temperature; main changes include loss secondary protein structure, cleavage sulphur bridges, dehydration, crosslinking rearrangements N-groups through formation carbodiimides. Oxidation at 300 °C rendered materials fibrous high yield (ca. 36 wt%), yielding carbonization temperatures.