Pre-treatment of Calotropis gigantea fibers with functional plasticizing and toughening auxiliary agents

Calotropis gigantea ( C. gigantea) has not yet been utilized in the textile industry due to its poor spinning capability. Here, we demonstrate the use of a functional auxiliary agent to improve the spinning possibility of C. gigantea fibers. Firstly, a functional plasticizing and toughening auxiliary agent (PTAA) with concentrations of 6%, 9%, and 12% (w/w) were sprayed on C. gigantea fibers, which were then dried at various drying temperatures for different drying periods. The physical properties, secondary structure, crystallization, and weight gain rate were examined before and after the processing treatment, and compared to another two commonly used commercial auxiliary agents, namely waterborne polyurethane and wook lubricating oil. The maximum breaking strength was achieved when the optimum concentration of the PTAA was 9 wt.%, the optimum drying temperature was 80℃, and the optimum time was 1 h. The C. gigantea fiber treated by the PTAA had better spinning possibility compared to the fibers treated by the other two commercial auxiliary agents in terms of weight gain rate ( p < 0.001), initial modulus ( p < 0.05), and reduced crystallinity (35.6%). The results showed that PTAA treatment is an effective way to improve the spinning possibility of C. gigantea fibers. The development of our new auxiliary agent and understanding of its effects on improving the spinning possibility of C. gigantea fibers could facilitate the development of C. gigantea fibers as a lignocellulosic raw material for applications in industrial textiles.