Electric-Field-Induced Actuation of Poly(vinyl alcohol) Microfibers

Abstract

Poly(vinyl alcohol) (PVA) microfibers were actuated by application of a direct current (dc) electric field; there were large electrosensitivity differences between water-soluble and high-tenacity fibers. In particular, a bending actuation was observed for water-soluble PVA fibers with high sensitivity and large deformation upon applying a dc electric field. The mechanism of bending actuation was investigated through analysis of the chemical constituents, dielectric properties, bending rigidity, and morphology. It was found that the actuation behavior depends mainly on the mechanical and dielectric properties, which are related to the chemical structures of the fibers. It is clear that hydroxyl and carbon−oxygen double bonds are key factors influencing the electroactive characteristics. The content of hydroxyl groups not only determines the solubility of PVA fibers in water but also controls the antielastic bending. The content of CO groups may be related to the dielectric constant and bending rigidity. Furthermore, the CS bond in the X-ray photoelectron spectrum indicates that dimethyl sulfoxide remains even after solvent removal, and this can make it easier for the PVA fibers to become positively charged and then bend toward the cathode.

New Shedding Motion, Based on Electroactuation Force, for Micro‐ and Nanoweaving

“…The actuation mechanism of PVA microfibers has been partly reported in previous papers . We developed water‐soluble PVA microfibers of diameter 18 μm (2.2 dtex) and with a dissolution temperature in water of 20 °C; we showed that the fibers have excellent actuation ability (bending by 1 mm to the cathode in just 0.4 s).…”

“…In previous work, we found that some synthetic polymer fibers have electroactive characteristics. The fibers were actuated and showed different behaviors under applied electric stimulation . In particular, polyvinyl alcohol (PVA) microfibers were bent in one direction (to the cathode side) by certain direct current (dc) voltages, with high electrosensitivity.…”

“…These fibers are suitable for actuation because of their high dielectric constant and good bending rigidity. The dimethyl sulfoxide (DMSO) remaining after spinning the fibers made it much easier for the PVA fibers to become positively charged and then bend toward the cathode. The bending mechanism is shown in Figure c.…”

Formation of polyketone particle structure by hexafluoroisopropanol solvent evaporation and effects of plasticizer addition

“…The response of a parallel circuit of resistance R and constant phase element (CPE) corresponding to an imperfect capacitor is a semicircle centered below the Z ′‐axis. R is determined from the diameter of the semicircle, and C is calculated from the maximum frequency of the semicircle . As shown in Figure (c–e), the diameters of the semicircles correspond to the interfacial resistances of the film and electrodes.…”

Design of a Dual‐Responsive Bilayered Actuator with Alternating Active Layers

“…The strong hydrophilic feature is quite related to the abundance of -OH in the PVA chains and also the highly porous structure. [44] Figure 2. Characterization of the bilayered porous PVA/PS film.…”