Silk Fibroin Based Magnetic Nanocomposites for Actuator Applications

Abstract

Recent technological and environmental advances are being redirected to develop technologies based on advanced materials that are not dependent on fossil fuels and/or critical elements. [1] Among them, smart materials showing piezoelectric, [2] piezoresistive, [3] photosensitive, [4] or magnetics properties, [5] among others, are particularly interesting for applications such as electronics, sensors, or actuators. Polymer composites stand out in the development of smart and multifunctional materials as polymer matrixes in which suitable fillers, i,e, metallic, ceramic, or magnetic micro/ nanoparticles, are incorporated, to tailor materials response toward specific applications. [6] Furthermore, those composites are often compatible with additive manufacturing technologies that enlarges their applicability. Different synthetic polymer matrices are being used in the development of polymer composites such as thermoplastics, thermosets or elastomers, but to reduce the processing and consumption of fossil fuels, biopolymers are increasingly being used. [7] Silk fibroin (SF) polymer has been investigated for biomedical, [8] energy storage, [9] and electronic applications [10] due to its excellent intrinsic characteristics. SF is a natural macromolecular protein produced in the specialized glades of Bombyx Mori silkworm. [11] SF is packed in cocoons and acts as shield versus foreign threats, solar radiation, temperature, humidity, parasites, and predators during the

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