Responsive Polymers as Sensors, Muscles, and Self-Healing Materials

Abstract

Responsive polymer-based materials can adapt to their surrounding environment by expanding and shrinking. This swelling and shrinking (mechanotransduction) can result in a number of functions. For example, the response can be used to lift masses, move objects, and can be used for sensing certain species in a system. Furthermore, responsive polymers can also yield materials capable of self-healing any damage affecting their mechanical properties. In this chapter we detail many examples of how mechanical responses can be triggered by external electric and/or magnetic fields, hygroscopicity, pH, temperature, and many other stimuli. We highlight how the specific responses can be used for artificial muscles, self-healing materials, and sensors, with particular focus on detailing the polymer response yielding desired effects.

Supramolecular Luminescent Sensors

“…Advantages of using nonconjugated polymers include the fact that there are more synthetic pathways available to access the broader variety of nonconjugated polymer backbones, including free radical polymerization, − step-growth polymerization, and ring-opening metathesis polymerization . Moreover, the nonconjugated backbone can have unique responsiveness to external stimuli, such as pH or temperature changes, which provides an additional handle for performance tunability and additional opportunities for sensing applications . Disadvantages include the lack of facile exciton migration and the resultant sensitivity that is promoted by conjugation .…”

“…1684 Moreover, the nonconjugated backbone can have unique responsiveness to external stimuli, such as pH 1685 or temperature changes, 1686 which provides an additional handle for performance tunability and additional opportunities for sensing applications. 1687 Disadvantages include the lack of facile exciton migration and the resultant sensitivity that is promoted by conjugation. 1688 Nonconjugated polymer backbones, by contrast, do not have facile exciton migration and are therefore unable to access the resulting gains in sensitivity and performance.…”

Constrained thermoresponsive polymers – new insights into fundamentals and applications

“…As a result of these environmental triggers, smart materials exhibit a defined reversible change in their physicochemical properties (e.g., solubility, viscosity) and can respond to stimuli in several ways by altering light transmitting abilities, shape, color, conductivity, as well as wettability [27,28]. Therefore, such functional polymers have a huge potential in numerous areas of application including biomedicine [29,30], drug delivery [12,31], tissue engineering [32,33], analytic application [18], environmental applications [34,35], sensors [36][37][38], actuators [37][38][39] and other applications [5].…”

The Challenges and Opportunities of Contemporary Polymer Mechanochemistry

“…[22] Such cascadesa re superior to simple one-step alternatives for exploitation in practical applications and fundamental studies of polymer behavior under load. [34][35][36] Some argued [37] that chemistry occupies ap rivileged place amongs ciences because it has the tools and conceptual frameworks that are uniquely suited to benefit ab road range of highly interdisciplinary problemsf acing humanity.P olymer mechanochemistry offersa no rganizingf ramework within which to exploit the sophisticated machinery of modern chemistry for designing molecules and reactionst od evelop broadly useful approaches for studying dynamics at length scales of 10-100 nm. [34][35][36] Some argued [37] that chemistry occupies ap rivileged place amongs ciences because it has the tools and conceptual frameworks that are uniquely suited to benefit ab road range of highly interdisciplinary problemsf acing humanity.P olymer mechanochemistry offersa no rganizingf ramework within which to exploit the sophisticated machinery of modern chemistry for designing molecules and reactionst od evelop broadly useful approaches for studying dynamics at length scales of 10-100 nm.…”

“…While most practical applications of polymer mechanochemistryr emain just proposals, few have been prototyped. [34][35][36] Some argued [37] that chemistry occupies ap rivileged place amongs ciences because it has the tools and conceptual frameworks that are uniquely suited to benefit ab road range of highly interdisciplinary problemsf acing humanity.P olymer mechanochemistry offersa no rganizingf ramework within which to exploit the sophisticated machinery of modern chemistry for designing molecules and reactionst od evelop broadly useful approaches for studying dynamics at length scales of 10-100 nm. In this so-called "formidable gap", separating the domains of traditionally atomistic and continuum descriptions of matter,t he existing tools to study the dynamic processes,o rc onceptual understandingo fh ow to describe them quantitativelya re particularly limited.…”