Entirely inkjet-printed flexible P(VDF–TrFE) based piezoelectric sensors and actuators have been fabricated and characterized.

Electrocaloric refrigeration is one of the most promising, environmentally-friendly technology to replace current cooling platforms-if a notable electrocaloric effect (ECE) is realized around room temperature where the highest need is. Here, we report a straightforward , onepot chemical modification of P(VDF-ter-TrFE-ter-CTFE) through the controlled introduction of small fractions of double bonds within the backbone that, very uniquely, decreases the lamellar crystalline thickness while, simultaneously, enlarging the crystalline coherence along the a-b plane. This increases the polarizability and polarization without affecting the degree of crystallinity or amending the crystal unit cell-undesirable effects observed with other approaches. Specifically, the permittivity increases by >35%, from 52 to 71 at 1 kHz, and ECE improves by >60% at moderate electric fields. At 40 C, an adiabatic temperature change >2 K is realized at 60 MVꞏm-1 (>5.5 K at 192 MVꞏm-1), compared to 1.3 K for pristine P(VDFter-TrFE-ter-CTFE), highlighting the promise of our simple, versatile approach that allows direct film deposition without requiring any post-treatment such as mechanical stretching or high-temperature annealing for achieving the desired performance. Enhanced Electrocaloric Response of Vinylidene Fluoride-based Polymers via One-Step Molecular Engineering

Supported lipid bilayers (SLBs) are cell-membrane-mimicking platforms of varying biological complexity, that can be formed on solid surfaces and used to characterise the properties of the plasma membrane or to...

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Fluorinated Electroactive Polymers (FEPs) are amongst the most interesting insulating materials for the production of organic electronic devices. Their ability to tune their response to an applied electric field makes them appropriate for vastly different applications in electronics. However due to the chemical inertness of such polymers and the rather complex synthetic processes required for their production, introducing additional functionality to FEPs remains an open challenge. Here we present a facile way to introduce additional functionality to FEPs and more specifically photopatternability by a simple etherification method, which allows us to introduce almost any functional group on FEPs. Photo cross-linkable moieties were introduced on FEPs using this method, inducing photopatternability, while tuning their electroactive response with great property enhancement up to 60% in terms of relative permittivity in several cases.

Relaxor ferroelectric polymers exhibit high k at their structural phase transition around room temperature. They are particularly attractive as gate dielectric in organic field effect transistor (OFET). Nevertheless, their applications are limited due to their low thermal stability. A polymer blend system with a high and thermally stable dielectric constant is demonstrated by mixing terpolymer poly(vinylidene fluoride‐trifluoroethylene‐chlorofluorethylene) P(VDF‐ter‐TrFE‐ter‐CFE) with copolymer poly(vinylidene fluoride‐trifluoroethylene) P(VDF‐co‐TrFE). PVDF‐based blends of various compositions are characterized by dielectric spectroscopy, differential scanning calorimetry (DSC), infrared spectroscopy, small and wide angle X‐ray scattering (SAXS and WAXS), and atomic force microscopy (AFM) in order to investigate the relationship between morphology and crystallization of the blend and their dielectric properties. An optimized blend of P(VDF‐ter‐TrFE‐ter‐CFE) [55/37/8] and P(VDF‐co‐TrFE) [46/54] at a ratio of 70/30 is found to exhibit a quasi‐constant dielectric constant of 40 ± 2 over a wide temperature range (20–80 °C). Furthermore, electrical characteristics of the PVDF‐blend‐based gate dielectric OFET show further thermal stability in comparison to OFET based on high‐k terpolymer P(VDF‐ter‐TrFE‐ter‐CFE) [55/37/8]. An improvement of their drain current stability by up to 60% is demonstrated at 60 °C. These findings enable broader applications of fluoropolymers in organic electronics.

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Blends of an aromatic copolymer bearing polar pyridine units in the main chain with sulfonated polysulfone (SPSF) were prepared in order to improve the copolymer's acid uptake and conductivity values. Depending on blend composition and sulfonation level miscible pairs were obtained as was studied by dynamic mechanical analysis. Blends of SPSF with sulfonation degree 70% and increased composition of the copolymer were selected for further study. The thermal and oxidative stability, the doping ability and the proton conductivity of the blends were also tested. Finally, an initial single cell test was performed with one of the prepared blends, showing promising results.