In this work, we report on the preparation of silk nanofibers using a combination of two top-down nanofibrillation techniques, Taylor-Couette flow (TCF) and aqueous counter-collision (ACC). The ACC system was used for the main nanofibrillation of silk...
In this work, we report on the preparation of silk nanofibers using a combination of two top-down nanofibrillation techniques, Taylor-Couette flow (TCF) and aqueous counter-collision (ACC). The ACC system was used for the main nanofibrillation of silk raw material (cocoon), and the TCF system was introduced as a pretreatment. The TCF treatment time and the number of ACC treatments were controlled as variables to increase the nanofibrillation efficiency. SEM analysis showed that the size and diameter of the silk nanofibers were effectively reduced as the TCF treatment time and the number of ACC passes increase. In particular, the TCF-based pretreatment enabled the direct processing of ACC with a concentrated silk suspension (0.3 w/v%), while only 0.1 w/v% was the highest condition possible without the TCF pre-treatment. This study suggests the possibility of improving the production efficiency of silk nanofibers by utilizing both TCF and ACC.