High-performance artificially reeled silkworm silk via a multi-task and high-efficiency centrifugal reeling technique and its application in soft actuators

Silkworm silks show increasing potential in applications of bioengineering, sensors, optics, electronics, and actuators. However, their inherent irregular morphologies, structures, and properties greatly hinder the translation of these technologies to commercial applications. Herein, we report a facile and comprehensive strategy to fabricate high-performance silk materials by spinning silkworms artificially via a multi-task and high-efficiency centrifugal reeling technique. With this strategy, centrifugally reeled silks (CRSs) with long-uniform morphologies, excellent strength (844.83 ± 319.48 MPa), high toughness (121.07 ± 35.31 MJ m^-3), and outstanding Young's modulus (27.72 ± 12.61 GPa) are developed. Remarkably, the maximum strength (1.45 GPa) of CRS is 3 times that of cocoon silk and even comparable to spider silk. Moreover, the centrifugal reeling technique realizes the one-step preparation of centrifugally reeled silk yarn (CRSY) from spinning silkworm, and the CRSYs show higher strength (877.38 ± 377.23 MPa) and superior torsional recovery performances. Furthermore, these CRSY-based soft pneumatic actuators (SPAs) exhibit light weight, high-loading capability, easy programmability in strength and motions, and fast responses, and therefore outperform currently reported elastomer-based SPAs, showing promising applications in flexible sensors, artificial muscles, and soft robotics. This work also provides a new guide for producing high-performance silks from silk-secreting insects and arthropods.