(698e) Using Stimuli-Responsive Polymers for Creating Self-Powered Autonomous “Intelligent” Systems

A chemical plant is a complex facility built by chemical engineers that involves analytical units (e.g., control system), regulatory units (e.g., pumps), and practical outputs (e.g., production of desired chemicals). Besides these large facilities, it is important to construct small-scale stand-alone functional systems. For example, electronic-based systems (e.g., machines and robots) together with artificial intelligence have a diverse range of important applications; however, electronic-based systems have their limitations (e.g., issues with powering and compatibility with various environments). Similar to the design and construction of a chemical plant, chemical engineers can contribute to the creation of advanced small-scale chemical systems that are not based on electronics for important applications.

This presentation discusses the approach of using stimuli-responsive polymers as basic building blocks for constructing self-powered autonomous “intelligent” systems. Intelligent systems are characterized by their ability to sense their environments, analyze surrounding signals, and provide a logical response. “Intelligent” systems usually consist of a combination of functions: the analytical processing functions, regulatory functions, and practical functions for responding to their surroundings (i.e., similar to designs of chemical plants). These functions can be constructed via designing the combination of stimuli-responsive polymers, physical-chemical phenomena, and reaction. For the analytical processing functions, we showed that the combination of a stimuli-responsive polymer and an asymmetric unsteady-state reaction diffusion allows the material to perform calculus: the temporal derivative of concentration of the medium. Hence, we showed that chemical systems with simple designs can perform advanced mathematical functions directly for the purpose of advanced control. We further showed that simple designs of assemblies of stimuli-responsive polymers can produce the functions of multiple logic gates for integrated circuits. For regulatory functions, stimuli-responsive polymers are designed to perform the functions of gating and self-amplification. For practical functions, simple designs of stimuli-responsive polymers are found to produce large amounts of force onto their surroundings. Despite being widely known as soft materials, these stimuli-responsive polymers are able to grip onto loads that are ~10,000 times more than their own weights. By functionalizing the surface of the stimuli-responsive polymers, they are shown to be able to target, capture, and rupture cancer cells. Self-powered autonomous “intelligent” systems can thus be fabricated by combining these different analytical, regulatory, and practical functions constructed out of stimuli-responsive polymers for carrying out complex analyses and operations for a wide range of applications.