PVDF-based electroactive polymer (EAP) actuators offer large field-induced strains, high compliance, and simple and scalable processing, enabling novel applications in soft robots, wearable devices, and medical devices. This work investigates how blending the poly(vinylidene fluoride−trifluoroethylene−chlorotrifluoroethylene) [P(VDF−TrFE−CTFE)] terpolymer with three phthalate-free plasticizers (butyryl trihexyl citrate (BTHC), 1,2-cyclohexanedicarboxylic acid diisononyl ester (DINCH), and tris(2-ethylhexyl) trimellitate (TOTM)) affects the electromechanical transduction properties. Thin films of plasticizer/terpolymer blends were obtained via stencil printing. Film morphology (SEM), crystallinity (XRD), and mechanical and dielectric properties were investigated at different plasticizer contents, and unimorph actuators were fabricated and characterized to quantify the field-induced transverse strains. The maximum strain increased by 12.5× over the neat terpolymer in TOTM 10 wt % blends, reaching 1% at 33.2 V/μm. The largest tip deflections were achieved with TOTM 5 wt %, giving 246.6 μm at 0.1 Hz and 1.65 mm at resonance (33.7 V/μm). At a fixed field of 18 V/μm, blends with BTHC 15 wt % and TOTM 10 wt % produced 3.8 and 4× strain improvements, while DINCH 5 wt % and TOTM 5 wt % delivered 1.48 and 2.2× higher deflections. DINCH- and TOTM-based actuators withstood at least 60% higher fields than the neat terpolymer, likely due to plasticizer diffusion into the EAP film pores. These results show that the studied plasticizers can enhance transduction in P(VDF−TrFE−CTFE), with further improvements expected by reducing film porosity, establishing optimal annealing processes and plasticizer concentrations.

High strains of the relaxor ferroelectric polymers allows to build efficient actuators. While the mechanical impedance of such actuators can be optimized via their morphology, their practical realization requires flexible and versatile fabrication processes. This work devises an efficient procedure for manufacturing unimorph bending actuators basing on the P(VDF-TrFE-CTFE) electroactive polymer (EAP). The fabrication process consists of inkjet printing the Ag electrodes and stencil printing the active P(VDF-TrFE-CTFE) layer. The effect of constituent layer dimensions and properties are analytically modelled to estimate the optimal morphology for highest strains. Actuators are manufactured on polyethylene naphthalate (PEN) and polyethylene terephthalate (PET) substrates and their performance is characterized. On PET substrate, the EAP layer thicknesses of 5 µm up to 24 µm are studied. The PEN-based actuators achieved up to 759 µm deflections in quasi-static (1 Hz, 560 V_pp) and up to 5.95 mm in resonant operation (52 Hz, 550 V_pp). The PET-based actuators achieved up to 486 µm deflections in quasi-static (1 Hz, 980 V_pp) and up to 4.44 mm in resonant operation (116 Hz, 700 V_pp). These results indicate an up to 123% improvement in quasi-static and 60% resonant actuation strains compared to the previously reported similar actuators. Modelling predicts that significantly larger deflections are feasible when fabricating the transducers with optimized morphology.

Dielectric elastomers (DEs) have received significant attention for their good performance among different smart material transducers. This study demonstrates the feasibility of fabricating dielectric elastomer actuators (DEAs) using exclusively inkjet printing technique. The manufactured unimorph bending cantilevers are composed of a polydimethylsiloxane (PDMS) active layer, sandwiched between two compliant electrodes, and printed onto a thin polyimide (PI) substrate. This study addresses the key fabrication challenges associated with inkjet printing such a layered actuator structure. This entails the consistent printing of the Ag electrodes on the smooth PI substrate, a PDMS layer on the Ag electrodes, the Ag electrodes on the smooth PDMS surface, and the respective steps of processing and curing. The fully inkjet-printed DEAs exhibited a maximum tip displacement of 36 µm in quasi-static operation (1 kV_pp) and 12.8 µm in resonant operation (50 Hz, 800 V_pp). This is the first time that inkjet-printing has been employed to print an entire dielectric elastomer actuator, broadening the outlooks to develop innovative devices that base on smart material transducers.