Combined application of multinozzle air-jet electrospinning and airflow twisting for the efficient preparation of continuous twisted nanofiber yarn

This paper presents a new approach for the mass production of nanofiber yarns, which involves the use of a multinozzle air-jet electrospinning system and airflow twisting. In this system, the aggregation, orientation, and continuous bundling of nanofibers are first achieved by applying the principle of conjugate electrospinning. Three-dimensional highspeed rotating airflow is then applied to continuously twist and spin the nanofibers into yarn. In this study, the mechanisms for formation and aggregation of nanofibers using the new air-jet electrospinning system were analyzed. In addition, numerical simulations of the airflow field within the nozzle were performed to understand the airflow characteristics and to study the effects of airflow twisting on nanofiber spinning. The obtained results indicated that the output of nanofiber bundles for the proposed multinozzle air-jet electrospinning system was able to reach 6.642 g/h. The application of three-dimensional rotating airflow enabled continuous production of twisted nanofiber yarns with favorable orientation and uniform twist distribution. Under an air pressure of 0.3 MPa and at a spinning speed of 132.1 m/s, the twist angle, tensile strength, and elongation of the nanofiber yarn were 65.2 °, 74.23 MPa, and 85.55 %, respectively. Thus, it can be concluded that the proposed spinning tenique is practical and efficient for high-speed and large-scale production of nanofiber yarn.