Dry‐Type Artificial Muscles Based on Pendent Sulfonated Chitosan and Functionalized Graphene Oxide for Greatly Enhanced Ionic Interactions and Mechanical Stiffness

Abstract

Biopolymer-based artifi cial muscles are promising candidates for biomedical applications and smart electronic textiles due to their multifaceted advantages like natural abundance, eco-friendliness, cost-effectiveness, easy chemical modifi cation and high electical reactivity. However, the biopolymerbased actuators are showing relatively low actuation performance compared with synthetic electroactive polymers because of inadequate mechanical stiffness, low ionic conductivity and ionic exchange capacity (IEC), and poor durability over long-term activation. This paper reports a high-performance electro-active nano-biopolymer based on pendent sulfonated chitosan (PSC) and functionalized graphene oxide (GO), exhibiting strong electro-chemomechanical interations with ionic liquid (IL) in open air environment. The proposed GO-PSC-IL nano-biopolymer membrane shows an icnreased tensile strength and ionic exchange capacity of up to 44.8% and 83.1%, respectively, and increased ionic conductivity of over 18 times, resulting in two times larger bending actuation than the pure chitosan actuator under electrical input signals. Eventually, the GO-PSC-IL actuators could show robust and high-performance actuation even at the very low applied voltages that are required in realistic applications.nano-biopolymer actuator that shows very large bending deformations under low input voltages in a dry environment. Scheme 1 . Schematic illustration for pendent sulfonated chitosan and graphene oxide-pendent sulfonated chitosan-ionic liquid (GO-PSC-IL) nano-biopolymer actuator.

Chitosan:poly (vinyl) alcohol composite alkaline membrane incorporating organic ionomers and layered silicate materials into a PEM electrochemical reactor

“…The total water uptake can induce significant swelling, being responsible of the dilution of the anions (OH -) concentration, which decreases the membrane conductivity, durability and the membrane performance in electrochemical devices [50]. Water uptake of membranes in the OH -form cannot be easily determined because of the various equilibrium reactions occurring [52].…”

Experimental study on critical heat flux of highly efficient soft hydrophilic CuO–chitosan nanofluid templates

“…The second, more severe weight loss, over the temperature range 270-390°C, was assigned to complex dehydration of the saccharide rings. The decomposition trend initiated between 290-469°C was responsible for depolymerization of the main chain; acetylated and deacetylated polymer unit decomposition occurs between 469°C and 800°C [12,21]. However, the thermal stability of the CuO-CS hybrid was higher than that of pure CS, due to the existence of thermally stable CuO.…”

“…The broad band at 3420 cm À1 corresponds to OH groups on the surface of the Cu metal. The stretching vibrational bands of the hydroxyl group, amine group, CH, amides I and II, C-N, and C-O-C appeared at 3320, 2900, 1545, 1627, 1416, and 1054 cm À1 , respectively [12,21,22]. In the case of CuO-CS NCs, Cu-NH and Cu-OH coordination diminished because the carbonyl groups that were anchored by coordination with Cu metal ions to form CuO-CS NCs networked layers, which appeared as a broad band at 3300 cm À1 and a mild peak at 2890 cm À1 , corresponded to stretching vibration of CH.…”

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

“…4) [42]. The GO-PSC-IL nano-biopolymer membrane shows an increased tensile strength with ionic exchange capacity up to 83.1% which increased ionic conductivity over 18 times.…”

“…After interpenetration of two poly [42] (3,4-ethylenedioxythiophene) (PEDOT) electrodes in both faces of the IPN film and swelling in an ionic liquid, a 20 μm thick conducting IPN actuator was obtained, which moved with large displacement at a 125 Hz fundamental frequency (Fig. 6).…”