Studies of the fibre structure and dyeing properties of Calotropis gigantea, kapok and cotton fibres

Calotropis gigantea, kapok and cotton fibres are all natural cellulose fibres, but the first of these is rarely used in textile fabrics. In this study, the structure and chemical composition of these three kinds of fibre were studied, and the dyeing properties of fabrics made from each of them were compared. The purpose of this was to provide a theory basis for the application of C. gigantea fibre in the textile industry. The surface morphology and cross-section of C. gigantea fibre in comparison with kapok and cotton were studied by scanning electron microscopy. Their fibrous structures were analysed by Fourier Transform-infrared spectroscopy and X-ray diffraction. The mechanical properties and water absorption capabilities were also measured and compared. Both C. gigantea fibre and kapok fibre exhibit a high degree of hollowness (80-90%), and no natural twist exists; there is a certain amount of lignin and hemicellulose in C. gigantea fibres; the crystallinity of C. gigantea fibres is 42.54%, and its crystallinity orientation index is 85.40%. C. gigantea fibre has the lowest tenacity but has the highest water content of the three kinds of fibre. The results of dyeing tests show that C. gigantea fabric has the lowest dye uptake and dye fixation.