Remote Propulsion of Miniaturized Mechanical Devices via Infrared‐Irradiated Reversible Shape Memory Polymers

Abstract

Remote propulsion of miniature mechanical devices possesses a great challenge to the scientific community. Herein, a lightweight two-way shape memory polymer (2WSMP)-based motor is presented, which operates a demo vehicle via a novel infrared-irradiated 2WSMP actuator. Most of the polymers that possess 2WSMP properties suffer from inadequate mechanical properties and low durability in harsh environments. Herein, the 2WSMP bilayer actuator, based on Kapton and polyPOSS (PP), possesses superior 2WSMP and mechanical properties, high lifting abilities, and durability in harsh environments. Kapton is well known for its outstanding physical properties. PP, a polyhedral oligomeric silsesquioxane (POSS)-based epoxy-like thermoset, possesses unique properties. Its advanced ability to maintain mechanical properties over a range of temperatures, while presenting a constant coefficient of thermal expansion, is essential for its 2WSMP actuation properties. The effects of the Kapton and PP layers? thickness on the force and deflection, generated by the 2WSMP actuators during heating, are studied. A theoretical model is used to predict the actuator's deflection, based on the layers? thickness. These actuators present excellent thermal stability at temperatures as high as 150?°C, while maintaining outstanding motion repeatability and extremely high lifting capacity of up to 6500 times of their own weight.