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Polyvinylidene difluoride (PVDF) has been demonstrated to possess considerable potential for significantly enhancing the ignition and combustion performance of boron and aluminum powders. Based on the extensive research on PVDF modified boron and aluminum energetic materials at home and abroad in recent years, ten mainstream techniques were summarized and refined, including solvent volatilization method, electrospinning technology, electrostatic spray technology, electrospray deposition method, microemulsion method, 3D printing technology, vacuum freeze-drying method, non-solvent induced phase separation method, liquid phase method and droplet microfluidic technology. Their preparation principles, application scenarios, advantages and disadvantages were described, the challenges of PVDF modified energetic materials were further pointed out, and the key directions for future research were proposed:1) safety improvements; 2) green technologies; 3) nanomaterial optimisation; 4) multi-scale design; 5) innovative coating methods; and 6) insight into reaction mechanisms.

The issue of low cathode conductivity is a significant challenge in battery development, particularly for automotive applications. The cathode plays a crucial role in Li-ion batteries, as it is responsible for transferring lithium ions during both charging and discharging processes. Therefore, this study aims to enhance the conductivity of the cathode by incorporating Acetylene Black (AB) and Polyvinylidene Difluoride (PVDF) additives. In this study, Nickel Manganese Cobalt (NMC) 811 and NMC 111 cathodes were used. These materials were formed into pellets, then made into sheets, with AB and PVDF additives added in a weight composition ratio of 85:10:5, and a coating thickness of 300 µm. The cathode conductivity was characterized using an LCR meter, while surface morphology, cross-section, EDS, and mapping of the cathode surface were analyzed with SEM. The results showed that the addition of additives increased the conductivity of NMC 111 by more than five times, from 23.27x10-8 S.cm-1 to 119.34x10-8 S.cm-1, and NMC 811 by more than twelve times, from 6.43x10-8 S.cm-1 to 81.79x10-8 S.cm-1. These findings suggest that higher particle density, improved size distribution, and smaller particle grains contribute to higher conductivity.

The widespread production and use of multi-fluorinated carbon-based substances for a variety of purposes has contributed to the contamination of the global water supply in recent decades. Conventional wastewater treatment can reduce contaminants to acceptable levels, but the concentrated retentate stream is still a burden to the environment. A selective anion-exchange membrane capable of capture and controlled release could further concentrate necessary contaminants, making their eventual degradation or long-term storage easier. To this end, commercial microfiltration membranes were modified using pore functionalization to incorporate an anion-exchange moiety within the membrane matrix. This functionalization was performed with primary and quaternary amine-containing polymer networks ranging from weak to strong basic residues. Membrane loading ranged from 0.22 to 0.85 mmol/g membrane and 0.97 to 3.4 mmol/g membrane for quaternary and primary functionalization, respectively. Modified membranes exhibited a range of water permeances within approximately 45–131 LMH/bar. The removal of PFASs from aqueous streams was analyzed for both "long-chain" and "short-chain" analytes, perfluorooctanoic acid and perfluorobutyric acid, respectively. Synthesized membranes demonstrated as high as 90% rejection of perfluorooctanoic acid and 50–80% rejection of perfluorobutyric acid after 30% permeate recovery. Regenerated membranes maintained the capture performance for three cycles of continuous operation. The efficiency of capture and reuse can be improved through the consideration of charge density, water flux, and influent contaminant concentration. This process is not limited by the substrate and, thus, is able to be implemented on other platforms. This research advances a versatile membrane platform for environmentally relevant applications that seek to help increase the global availability of safe drinking water. [ABSTRACT FROM AUTHOR]

The application of terahertz (THz) science in industrial technology and scientific research requires efficient THz detectors. Such detectors should be able to operate under various external conditions and conform to existing geometric constraints in the required application. Pyroelectric THz detectors are among the best candidates. This is due to their versatility, outstanding performance, ease of fabrication, and robustness. In this paper, we propose a compact pyroelectric detector based on a bioriented poled polyvinylidene difluoride film coated with sputtered metal electrodes for in situ absorption measurement at cryogenic temperature. The detector design was optimized for the registration system of the electron paramagnetic resonance (EPR) endstation of the Novosibirsk Free Electron Laser facility. Measurements of the detector response to pulsed THz radiation at different temperatures and electrode materials showed that the response varies with both the temperature and the type of electrode material used. The maximum signal level corresponds to the temperature range of 10–40 K, in which the pyroelectric coefficient of the PVDF film also has a maximum value. Among the three coatings studied, namely indium tin oxide (ITO), Au, and Cu/Ni, the latter has the highest increase in sensitivity at low temperature. The possibility of using the detectors for in situ absorption measurement was exemplified using two typical molecular spin systems, which exhibited a transparency of 20–30% at 76.9 cm−1 and 5 K. Such measurements, carried out directly in the cryostat with the main recording system and sample fully configured, allow precise control of the THz radiation parameters at the EPR endstation. [ABSTRACT FROM AUTHOR]

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Three-phase polymer composites are promising materials for creating electronic device components. The qualitative and quantitative composition of such composites has a significant effect on their functional, in particular dielectric properties. In this study, ceramic filler K2Ni0.93Ti7.07O16 (KNTO) with Ag coating as conductive additive (0.5, 1.0, 2.5 wt.%) was introduced into the polyvinylidene difluoride (PVDF) polymer matrix in amounts of 7.5, 15, 22.5, and 30 vol.%. to optimize the dielectric constant and dielectric loss tangent. The filler was characterized by X-ray phase analysis, Fourier-transform infrared spectroscopy and Scanning electron microscopy methods. The dielectric constant, dielectric loss tangent, and conductivity of three-phase composites KNTO@Ag-PVDF were studied in comparison with two-phase composites KNTO-PVDF in the frequency range from 102 Hz to 106 Hz. The dielectric constant values of composites containing 7.5, 15, 22.5, and 30 vol.% filler were 12, 13, 17.4, 19.2 for pure KNTO and 13, 19, 25, 31 for KNTO@Ag filler (2.5 wt.%) at frequency 10 kHz. The dielectric loss tangent ranged from 0.111 to 0.340 at a filler content of 7.5 to 30 vol.%. A significantly enhanced balance of dielectric properties of PVDF-based composites was found with K2Ni0.93Ti7.07O16 as ceramic filler for 1 wt.% of silver. Composites KNTO@Ag(1 wt.%)-PVDF can be applied as dielectrics for passive elements of flexible electronics. [ABSTRACT FROM AUTHOR]

The development of efficient and reliable sensors operating at room temperature is essential to advance the application of terahertz (THz) science and technology. Pyroelectric THz detectors are among the best candidates, taking into account their variety, outstanding performance, ease of fabrication, and robustness. In this work, we compare the performance of six different detectors, based on either LaTiO3 crystal or different polymeric films, using monochromatic radiation of the Novosibirsk Free Electron Laser facility (NovoFEL) in the frequency range of 0.9–2.0 THz. The main characteristics, including noise equivalent power and frequency response, were determined for all of them. Possible reasons for the differences in the obtained characteristics are discussed on the basis of the main physicochemical characteristics and optical properties of the sensitive area. At least three detectors showed sufficient sensitivity to monitor the shape and duration of the THz macropulses utilizing only a small fraction of the THz radiation from the primary beam. This capability is crucial for accurate characterization of THz radiation during the main experiment at various specialized endstations at synchrotrons and free electron lasers. As an example of such characterization, the typical stability of the average NovoFEL radiation power at the beamline of the electron paramagnetic resonance endstation was investigated. [ABSTRACT FROM AUTHOR]

Technological developments and innovations in the wearable device field have created huge consumer demand. Hence, designing energy harvesting devices are of utmost importance. Of the various types of energy harvesting devices, triboelectric nanogenerators (TENGs) have come to the fore, as it can efficiently harvest electrical energy from mechanical motions. To date, polymers and metals have dominated the triboelectric series, but there is a need to develop novel composite materials and 2D materials to enhance the performance of TENGs. In this study, electrospun polyacrylonitrile nanofibers are prepared and decorated with zeolitic imidazole framework‐67 (ZIF‐67@PAN) to form pearl‐necklace‐like fibers. ZIF‐67@PAN nanofibers are prepared by immersing PAN nanofibers for different hours (1, 5, 10, and 24 h) in ZIF‐67 solution, they provide more roughness, and efficient surface contact area. The immersion of PAN fibers in ZIF solution for longer times increases overall energy harvesting efficiency. Different amounts of MXene are deposited on PVDF; the inclusion of MXene improves the charge transfer properties of TENGs. PAN@ZIF‐67 is used as a positive tribolayer and PVDF@MXene as a negative tribolayer. The optimized TENG device has 305 V, 10.6 µA, and 10.9 W/m2 power and demonstrated promising energy harvesting characteristics and self‐powered sensing efficiency. [ABSTRACT FROM AUTHOR]

In this study, electrically conductive composites of ethylenedioxythiophene-based terpolymer (PETCH), polyvinylidene difluoride (PVDF) and graphene nanosheets (GNS) have been prepared by compression molding and characterized. A new conjugated PETCH polymer was synthesized and its chemical structure has been confirmed by Fourier transform infrared and 1H-NMR spectroscopy. The varying weight percentages of (1, 3 and 5%) GNS and 10 wt% PETCH dispersed PVDF nanocomposites were prepared and characterized using X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDX) analysis. The thermal studies indicated that the decomposition occurred at a temperature around 220°C, and 480°C corresponds to the PETCH and PVDF/PETCH/GNS (1, 3 and 5%), respectively. The EDX spectrum of neat PETCH polymer and their composites of PVDF/PETCH/GNS (1, 3 and 5%) result clearly shows the presence of all elements such as, C, O, S, F and Cl with an atomic weight percentage. The PVDF/PETCH/5% GNS has a dielectric constant value of 3.9 at 1 MHz and the conductivity of this polymer composites value is found to be 5.8 × 10–6 S cm–1 at 1 MHz, respectively. Results obtained from the dielectric studies indicated that the GNS and terpolymer-dispersed PVDF composites exhibit good interfacial adhesion as evidenced from conductive behaviours. [ABSTRACT FROM AUTHOR]

In this work, polyvinylidene fluoride (PVDF) and graphene oxide (GO) composite membranes were fabricated using electrospinning technology for particulate matter (PM) filtration. The preparation conditions like GO oxidation time, electrospinning solution composition, and GO content in the composite film, and the basic properties and filtration performance of PVDF–GO films were systematically analyzed. It was found that GO with lamellar structure was of great benefit to endow the membrane with excellent mechanical properties and particle capture capacity. The as-prepared PVDF–GO membranes with GO addition of 0.6 wt.% exhibited the highest tensile strength and PM filtration efficiency. This work demonstrated that blending GO in PVDF is a feasible modification to fabricate an effective PM filtration membrane. [ABSTRACT FROM AUTHOR]

• PVDF materials are used in SUI and POP surgery. • Although the study results are limited by the low quality of the existing data, PVDF tapes appear to be associated with lower de-novo urgency compared to PP tapes after surgical treatment of SUI, • PVDF meshes appear to be associated with lower de-novo sexual dysfunction compared to PP meshes after surgical treatment of POP. • No difference is found regarding post-operative pain, recurrence and erosion rates between PVDF and PP surgery for SUI or POP. Synthetic materials have been used for the surgical treatment of stress urinary incontinence (SUI) and pelvic organ prolapse (POP). During the last 25 years, these materials were composed mostly of polypropylene (PP), whereas recently the use of polyvinylidene difluoride (PVDF) is of increasing interest due to its characteristics. This study aimed to compare the results after SUI/POP surgery using PVDF versus PP materials by synthesizing the data of relevant existing literature. This systematic review and meta -analysis included clinical trials, case-control studies, or cohort studies written in the English language. The search strategy included the electronic databases MEDLINE, EMBASE, and Cochrane, and grey literature (congresses IUGA, EUGA, AUGS, FIGO). All studies have to provide numeric data or odds ratios (OR) of developing a specific outcome in surgeries with PVDF compared with outcomes of other used materials. No restrictions of race or ethnicity were applied, nor chronological restrictions. Exclusion criteria were studies that included patients with cognitive impairment, dementia, stroke, or central nervous system trauma. All studies were screened by two reviewers, initially by title and abstract, and afterward by full text. Disagreements were resolved through mutual consent. All studies were assessed for their quality and bias risk. Data were extracted using a data extraction form formulated in a Microsoft Excel spreadsheet. Our results were divided into studies dealing only with SUI patients, studies dealing only with POP patients, and cumulative analysis of variables expressed in both SUI and POP surgery. The primary outcomes were the rates of post-operative recurrence, mesh erosion, and postoperative pain after surgery with PVDF compared to PP. The secondary outcomes were post-operative sexual dissatisfaction, overall satisfaction rates, hematoma, urinary tract infection, de novo urge incontinence, and reoperation rate. No differences in the post-operative rates of SUI/POP recurrence, mesh erosion, and pain were found after surgery with PVDF vs surgery with PP. Patients after SUI surgery with PVDF tapes had statistically significant lower rates of de-novo urgency compared to the PP group [OR = 0.38 (0.18, 0.88), p = 0.01]; patients after POP surgery with PVDF materials had statistically significant lower rates of de-novo sexual dysfunction compared to the PP group [OR = 0.12 (0.03, 0.46), p = 0.002]. This study provided evidence that the use of PVDF in SUI/POP surgeries could be a valid alternative to PP. However our results are limited by uncertainty due to the overall low quality of the existent data. Further research and validation would contribute to better surgical techniques. [ABSTRACT FROM AUTHOR]

Particulate matter (PM), especially with particle diameter below 2.5 µm (PM2.5), causes serious impacts on human health. Nanofibrous filters are one of the most widely investigated materials for the filtration of PM2.5 and viruses from the air at high efficiency. Recent concerns regarding energy efficiency of air control units dictated that a high-performance air filter should not only provide high filter efficiency, but also low pressure drop and longer operational service. Herein, PA6- and PVDF-based nanofibrous filter media for particle filtration via modified solution-blowing (m-SB) system with two separate nozzles was produced. Depending on the concentration, the average fiber diameters for PA6 and PVDF alternated nearly 70–137 and 122–230 nm, respectively. After optimization of the production parameters for each polymer to obtain less droplet density and high fiber content, the mechanical and filtration performance of the composite filter structures produced by blowing two polymers simultaneously were investigated. According to results, the highest and lowest mechanical performance was obtained from PVDF-20 and PA6-20 samples while the composite nanofibrous sample (PA/PVDF-5) was exhibited a value between them. However, contrary to expectations, the increased production time (PA/PVDF-10 sample) caused a decrease in the mechanical properties of the composite samples. This could be attributed to the abrasive effect of the twofold amount of air coming to the same point per unit of time on the fibrous mat because of simultaneous usage of two nozzles. On the other hand, the filtration efficiency of PA6/PVDF-10 composite filter mat was found superior with 93% efficiency and 194 Pa pressure drop values. Although this efficiency was very close to the efficiency from PVDF-20 sample, the composite sample was 150% thinner. [ABSTRACT FROM AUTHOR]

In this study, we report the effect of intercalation of dimethyl sulfoxide (DMSO) and urea molecules into the interlayer space of Ti3C2Tx MXene on the dielectric properties of poly(vinylidene fluoride) (PVDF)/MXene polymer nanocomposites. MXenes were obtained by a simple hydrothermal method using Ti3AlC2 and a mixture of HCl and KF, and they were then intercalated with DMSO and urea molecules to improve the exfoliation of the layers. Then, nanocomposites based on a PVDF matrix loading of 5–30 wt.% MXene were fabricated by hot pressing. The powders and nanocomposites obtained were characterized by using XRD, FTIR, and SEM. The dielectric properties of the nanocomposites were studied by impedance spectroscopy in the frequency range of 102–106 Hz. As a result, the intercalation of MXene with urea molecules made it possible to increase the permittivity from 22 to 27 and to slightly decrease the dielectric loss tangent at a filler loading of 25 wt.% and a frequency of 1 kHz. The intercalation of MXene with DMSO molecules made it possible to achieve an increase in the permittivity up to 30 at a MXene loading of 25 wt.%, but the dielectric loss tangent was increased to 0.11. A discussion of the possible mechanisms of MXene intercalation influence on the dielectric properties of PVDF/Ti3C2Tx MXene nanocomposites is presented. [ABSTRACT FROM AUTHOR]

This study reports the feasibility of recycled polyvinylidene difluoride (PVDF) beads to decolourize methylene blue (MB) from aqueous streams. The beads were characterized using scanning electron microscopy (SEM), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT-IR) for its morphological and structural analysis. The effect of various process parameters such as adsorbent dose, initial concentration, contact time, and pH was studied. The first principle density functional theory (DFT) calculations were performed to investigate the underlying mechanism behind the adsorption process. The MB dye adsorption on recycled PVDF beads followed the pseudo-second-order kinetics and Langmuir isotherm, indicating the adsorption was chemical and monolayer. The maximum adsorption capacity obtained was 27.86 mg g−1. The adsorption energy of MB-PVDF predicted from the DFT study was –64.7 kJ mol−1. The HOMO-LUMO energy gap of PVDF decreased from 9.42 eV to 0.50 eV upon interaction with MB dye due to the mixing of molecular orbitals. The DFT simulations showed that the interaction of the MB dye molecule was from the electronegative N atom of the MB dye molecule, implying that electrostatic interactions occurred between the recycled PVDF beads and the positively charged quaternary ammonium groups in MB dye. The present study demonstrates the potential of recycled PVDF beads for a low-cost dye removal technique from textile wastewater. HIGHLIGHTS Experiments and DFT calculations were performed to evaluate the binding of MB dye to PVDF beads synthesized from used membranes.; The adsorption of MB dye on PVDF beads was monolayer and chemical in nature, with a maximum adsorption capacity of 27.86 mg g−1.; The DFT study predicted the adsorption energy of 64.7 kJ mol−1 for MB-PVDF, indicating the strong interaction between MB dye and PVDF.; The study demonstrated the potential of recycled PVDF beads for a low-cost dye removal technique.;

Lithium batteries have been widely used in portable appliances and medical and aerospace devices, and further improving the energy density and power density is of great significance to the future development of related technologies. In this work, a high-dielectric polyvinylidene difluoride (PVDF) coating film was designed and realized on Cu foil by a polar solution-induced phase transition method. The PVDF40 coating film prepared at 40 °C displays a high β-phase content (91.68 %) and strong dielectric properties, which can effectively promote the dissociation of Li salt, and exhibits superior ionic conductivity of 4.06 × 10−4 S cm−1 and greatly increased Li transference number of 0.652. The Li-CF x battery with coating film delivers an excellent specific discharge capacity of 947 mAh g−1 at 0.1C, and a superior rate capacity of 634 mAh g−1 even at 5C, attributed to the improved dissociate of lithium salt, Li coordination environment and ion transport. This study demonstrates a dielectric film protection strategy to achieve high-performance lithium batteries. [Display omitted] • β-phase PVDF is controllably synthesized by a polar solvent induction method. • The dielectric PVDF improves Li salt dissociation and Li+ transference number. • High ionic conductivity of 4.06 × 10−4 S cm−1 is obtained. • The assembled Li-CF x battery demonstrates outstanding capacity and rate performance. [ABSTRACT FROM AUTHOR]

The present study describes the optical properties for prepared polymer nanocomposites of PVDF at different content of MoO3/g-C3N4. The structural properties of polymer films were analysed via XRD, FTIR and ESEM techniques. The XRD diffraction patterns of PVDF with different concentrations of MoO3/g-C3N4 have two characteristic peaks at 2 θ = 18.4° and 20.3° where first peak was assigned to α-phase, while last peak was attributed to β-phase. The ESEM micrographs of PVDF-MoO3/g-C3N4 nanocomposites have shown smooth surface topography. According to the UV–visible absorption spectra, the UV absorption of PVDF was increased when adding MoO3/g-C3N4 nanoparticles where distinct peak was appeared in the UV region at 310 nm and its edges become more intense and moved towards higher wavelength after MoO3/g-C3N4 incorporation. The optical values of (Edir) and (Eind) energies have decreased with increasing the nanoparticle composites content. The optical band gap energy (Eopt) was decreasing from 5.66 eV to 4.56 eV as increasing the content of MoO3/g-C3N4. The refractive index (n) was increased with increasing the concentration of MoO3/g-C3N4 in nanocomposites samples, except for the sample with 0.25 wt%. The distinctive optical characteristics of PVDF-MoO3/g-C3N4 qualify such polymer nanocomposites for optoelectronic applications.

We have developed conductive, lightweight, and porous composite of polyvinylidene difluoride by blending with synthesized conjugated terpolymer and graphene for conductive polymer composite applications. The new conjugated terpolymer designated as PEPy-TP is synthesized from 3,4-ethylenedioxythiophene, 1-pyrenecarboxzaldehyde, and heptaldehyde through friedel craft reaction. The synthesized terpolymer PEPy-TP have been blended with polyvinylidene difluoride and graphene nanosheets to form porous composite and has been characterized using XRD, TGA, TG-DSC, DTA, DTG, SEM, EDX, and Dielectric spectroscopy. The porous composite is comprised of varying weight percentages of (1, 3, and 5%) of GNS and 10 wt% PEPy-TP in PVDF. The thermal studies on the porous composites indicated that the decomposition occurred at a temperature around 270 and 470 °C corresponds to the PEPy-TP and PVDF/PEPy-TP/GNS (1, 3, and 5%), respectively. The EDX spectrum of neat PEPy-TP polymer and their porous composites of PVDF/PEPy-TP/GNS (1, 3, and 5%) result clearly shows the presence of all elements, such as C, O, S, and F with an atomic weight percentage also. The PVDF/PEPy-TP/5% GNS porous composites having a tremendous electrical conductivity and the dielectric constant value is 56 at 1 MHz and their conductivity of this polymer porous composites value is determined to be 4.9 × 10−6 S/cm at 100 kHz, respectively. [ABSTRACT FROM AUTHOR]

With industry development, the separation of oily wastewater is becoming more critical. Inspired by organisms such as lotus leaves, biomimetic superhydrophobic surfaces with micro-nano structures have shown great potential in this regard. In this work, PDMS/PVDF oil–water separation membranes with designed microstructures were prepared by electrospinning technology. The membrane-forming effect of electrospinning with different ratios of PDMS and PVDF was studied. The study found that membranes with high PDMS content were more likely to form microspheres, and PDMS tended to concentrate on the microspheres. The results also showed that the microspheres would bring better hydrophobicity to the membrane. When the ratio of PDMS to PVDF is 1:2, the membrane has a water contact angle of up to 150° and an oil contact angle of 0°. At this ratio, the separation efficiency of the membrane for the water-in-oil emulsion is 98.7%, and it can still maintain more than 98% after ten separation cycles, which is a good candidate for oil–water separation. Furthermore, microspheres enable the membrane to achieve macroscopic uniformity and microscopic phase separation so that the membranes have both good elongation and fracture strength. In addition, the PDMS/PVDF membranes also exhibit excellent UV resistance, and their UV protection factor is greater than 185, making them a potential UV protective material. [ABSTRACT FROM AUTHOR]

New three-phase composites, destined for application as dielectrics in the manufacturing of passive elements of flexible electronics, and based on polymer (PVDF) matrix filled with powdered ceramics of the hollandite-like (KFTO(H)) structure (5.0; 7.5; 15; 30 vol.%) and carbon (MWCNT) additive (0.5; 1.0; 1.5 wt.% regarding the KFTO(H) amount), were obtained and studied by XRD, FTIR and SEM methods. Chemical composition and stoichiometric formula of the ceramic material synthesized by the sol–gel method were confirmed with the XRF analysis data. The influence of the ceramic and carbon fillers on the electrical properties of the obtained composites was investigated using impedance spectroscopy. The optimal combination of permittivity and dielectric loss values at 1 kHz (77.6 and 0.104, respectively) was found for the compositions containing K1.6Fe1.6Ti6.4O16 (30 vol.%) and MWCNTs (1.0 wt.% regarding the amount of ceramic filler). [ABSTRACT FROM AUTHOR]

The polyvinylidene difluoride + barium titanate (BaTiO3) +graphene composite (PBGC) is one of the widely explored thermoplastic matrix due to its 4D capabilities. The number of studies has been reported on the process parameters of twin-screw extruder (TSE) setup (as mechanical blending technique) for the development of PBGC in 3D printing applications. But, hitherto, little has been reported on chemical-assisted mechanical blending (CAMB) as solution mixing and melt mixing technique combination for preparation of PBGC. In this work, for preparation of PBGC feedstock filaments, CAMB has been used. Also, the effect of process parameters of TSE on the mechanical, dimensional, morphological, and thermal properties of prepared filament of PBGC have been explored followed by 3D printing. Further, a comparative study has been reported for the properties of prepared filaments with mechanically blended composites. Similarly, the mechanical properties of 3D printed parts of chemically and mechanically blended composites have been compared. The results of tensile testing for CAMB of PBGC show that the filament prepared with 15% BaTiO3 is having maximum peak strength 43.00 MPa and break strength 38.73 MPa. The optical microphotographs of the extruded filaments revealed that the samples prepared at 180°C extruder temperature and 60 r/min screw speed have minimum porosity, as compared to filaments prepared at high extruder temperature. Further, the results of the comparative study revealed that the filaments of CAMB composites show better mechanical properties as compared to the filaments of mechanically mixed composites. However, the dimensional properties were almost similar in both cases. It was also found that the CAMB composites have better properties at low processing temperature, whereas mechanically blended composites show better results at a higher temperature. While comparing 3D printed parts, tensile strength of specimens fabricated from CAMB was more than the mechanically blended PBGC. [ABSTRACT FROM AUTHOR]

We present piezoelectric hybrid nanofibers capable of monitoring human movement, focusing on the effects of GO and rGO on the β-phase of PVDF. The β-phase in rGO is enhanced through polymer-assisted dispersion, leading to enhanced output voltage. Dispersants are used to reduce rGO aggregation, improve stability, and further boost β-phase content. Through the fabrication of piezoelectric hybrid nanofiber sensors, we successfully integrate electrospinning technology with wearable football sensors. The electrospun TX-100/rGO/PVDF piezoelectric hybrid nanofibers exhibit excellent hydrophobicity, self-powering properties, and flexibility, making them well-suited for football position sensor monitoring. [Display omitted] • Interfacial interactions enhance the β-phase crystallization of PVDF. • Triton X-100 dispersed rGO improves β-phase crystallinity and enhances electrical properties. • The synergistic effect of rGO significantly increases the output voltage. • The PENG exhibits high durability. • PENGs can be used as sensors or energy harvesters. Electrospun graphene oxide (GO)/polyvinylidene difluoride (PVDF) and reduced graphene oxide (rGO)/PVDF piezoelectric hybrid nanofibers were prepared via electrospinning to enhance the β-phase content of the PVDF crystal structure. The addition of rGO increased the number of nucleation sites in the PVDF matrix, leading to an improved β-phase content in the nanofibers. Although the inclusion of GO also increased the β-phase content, rGO addition resulted in higher output voltages due to its greater conductivity compared to GO. rGO/PVDF produced higher output voltages than GO/PVDF because rGO has few oxygen-containing groups on its carbon atoms. The 1 wt% GO/PVDF nanofibers exhibited an 86.24 % β-phase content and an average output voltage of 3.2 V under a 15 N load. The 0.5 wt% rGO/PVDF nanofibers demonstrated an 84.09 % β-phase content and an average output voltage of 3.66 V under the same load. The nonionic surfactant Triton X-100 improved rGO dispersal, enhancing its effectiveness in inducing β-phase formation, and increasing the number of stress concentration points in the nanofibers. A piezoelectric device composed of TX-100/rGO/PVDF nanofibers exhibited stable performance even after 1,500 load cycles, generating an average output voltage of 7.13 V under a 15 N load. This device serves as both an energy harvester and a footwear sensor, offering potential applications in new sports monitoring technologies and self-powered wearables. [ABSTRACT FROM AUTHOR]

Piezoelectric tactile sensors are widely adopted to detect vibration and other stimuli. Among them, Polyvinylidene fluoride (PVDF) has the advantage of high flexibility, fast response and low cost. However, its sensitivity is restricted by the traditional d 33 working mode. Herein, we proposed a rigid-in-soft structure with truncated pyramid shape and soft bottom layer to enhance the force-transmission efficiency. This design synergizes the d 33 working mode and d 31 working mode, thereby surpassing the sensitivity limit. The mechanism has been analyzed using Finite Element Modeling (FEM), and experiment results indicate that rigid-in-soft tactile sensor exhibits a sensitivity of 35.6 mV/N, along with a linear force detection range of 1–11 N. The sensitivity is approximately 1.7 times higher than that of control sensor without rigid pillar. Furthermore, the sensor displays a great flexibility and reliability, making it highly promising for detecting dynamic stimuli in robotics, such as slip and vibration. [Display omitted] • A rigid-in-soft structure is proposed to increase force transmission efficiency and trigger d 31 working mode. • The working mechanism of rigid-in-soft tactile sensor is illustrated by FEA and verified through experiments. • The sensor proves to be able to detect slip and monitor grasping conditions while attached to a parallel gripper. [ABSTRACT FROM AUTHOR]

Piezoelectric material is a kind of intelligent material which can generate voltage when the material is deformed. Polyvinylidene fluoride (PVDF) is widely studied for its excellent piezoelectric properties. Firstly, the crystal structure of polyvinylidene difluoride molecular was studied by middle infrared (MIR) spectroscopy. The crystal structure of polyvinylidene difluoride molecular includes α crystal structure, β crystal structure and γ crystal structure. Secondly, Temperature-dependent middle infrared (TD-MIR) spectroscopy and two dimensional middle infrared (2D-MIR) spectroscopy of polyvinylidene difluoride molecular were studied. With the increase of the temperature from 303 K to 523 K, the corresponding frequency and absorption intensity of polyvinylidene difluoride molecular crystal structure changed obviously, the crystal structure of polyvinylidene difluoride molecular was sensitive to the temperature. The crystal structure interchange mechanism was studied at length. The three-step MIR spectroscopy (MIR, TD-MIR and 2DMIR) can broaden the scope of the analysis of crystal structure and thermal denaturation of the important functional polymer materials with piezoelectric properties (polyvinylidene difluoride). [ABSTRACT FROM AUTHOR]

This study uses near-field electrospinning (NFES) technology to make a novel self-powered strain sensor and applies it to the real-time monitoring of a bending structure, so that the measurement equipment can be reduced in volume. A self-powered strain sensor consists of polyvinylidene difluoride (PVDF) fibers, a PDMS fixed substrate, and an aluminum electrode. PVDF fibers are spun with DMSO and acetone using NFES technology, with a diameter of about 8 μm, Young's modulus of 1.1 GPa, and piezoelectric effect of up to 230 mV. The fixed substrate is a film made of PDMS by thermal curing, then adhered to the PDMS film surface of the sheet Al metal as an Al electrode, and then combined with PVDF fiber film, to become a self-powered strain sensor. As a result, the XRD β value of the self-powered strain sensor reaches 2112 and the sensitivity is increased by 20% over a traditional strain sensor. The cumulative angle algorithm can be applied to measure the angular change of the object over a unit of time or the cumulative displacement of the object over the entire period of motion. The experimental results demonstrate that the self-powered strain sensor combined with the angle accumulation algorithm may be applied to monitor the bending structure, thereby achieving continuous measurements of bending structure changes, and improving on traditional piezoelectric sensors, which can only be sensed once. In the future, self-powered strain sensors will have the ability to continuously measure in real-time, enabling the use of piezoelectric sensors for long-term monitoring of structural techniques. [ABSTRACT FROM AUTHOR]

As emerging eutectic mixtures, deep eutectic electrolytes (DEEs) show unique properties for Li‐metal batteries (LMBs). However, the limited choice and inferior electrode compatibility hinder their further development in LMBs. Herein, we report a new 1,2‐dimethylimidazole (DMIm)‐based deep eutectic gel polymer electrolyte induced by Li−N interaction. We demonstrate that incorporating electron‐withdrawing polyvinylidene difluoride (PVDF) polymer into the DMIm‐based DEE changes the coordination environment of Li+ ions, leading to a high transference number of Li+ ions (0.65) and superior interface stability between the electrolyte and Li anode. The deep eutectic gel polymer electrolyte exhibits excellent non‐flammability, high ionic conductivity (1.67 mS cm−1 at 30 °C), and high oxidation voltage (up to 4.35 V vs. Li/Li+). The Li||LFP cell based on the newly developed deep eutectic gel polymer electrolyte can achieve superior long‐term cycling stability at a wide range of rates. [ABSTRACT FROM AUTHOR]

Water pollution, resulting from the degradation of plastics into microplastics, exposes humans and other living organisms to contaminated drinking water. Microplastics are capable of adsorbing toxic heavy metals which are carcinogenic and may affect the reproductive functions of living organisms. Hence, this study focuses on the characterization and quantification of microplastics in water to raise the awareness and propose a method of dealing with this emerging pollutant in various aqueous environments. The microplastics were separated from water using polyvinylidene difluoride (PVDF) and PVDF modified with carbon nano-onions (CNOs). The PVDF exhibited the highest concentration of microplastics in the wastewater influent (140 ± 1.85 MP/L) compared to the effluent (8.8 ± 2.10 MP/L), tap water (6.5 ± 5.77 MP/L), and lake water (10 ± 2.65 MP/L). The stereo microscope displayed red, blue, and black colored plastics. The morphological properties were determined using SEM. ATR-FTIR, equipped with Spectrum 10 Spectroscopy Software was used to establish the presence of high-density polyethylene (50%), poly(1,4-butylene terephthalate) (16.6%), nylon 12 (16.6%), and cellulose (16.6%) in the influent. The quantification of heavy metals extracted from the microplastics indicated that the concentrations of As (1.759 to 8.699 mg/L), Cu (83.176 mg/L) and Zn (0.610 mg/L) were above the acceptable limits. Our work is beneficial for the development of a microplastics monitoring protocol for various municipalities. Water treatment plants may also include the treatment of microplastics in the influent and monitor the effluent before the water is released back into the environment. [ABSTRACT FROM AUTHOR]

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A simple and delicate approach was developed for the determination of duloxetine hydrochloride using electrospun polyvinylidene difluoride (PVDF) nanofibers. Synthesis of PVDF-based electrospun nanofibers was monitored by ultraviolet visible (UV) spectrophotometer. The characterization was carried out by atomic force microscopy (AFM) and Fourier transform infrared (FTIR) spectroscopy. AFM images showed that the size of synthesized PVDF electrospun nanofibers ranged in between 20 and 340 nm, while the presence of different functional groups was confirmed by FTIR spectroscopy. The synthesized PVDF electrospun nanofibers were applied for the determination of duloxetine hydrochloride. For the determination of duloxetine hydrochloride, a calibration of the standards of known concentration of duloxetine hydrochloride ranging from 1 to 10 mg/L in PVDF electrospun nanofibers solution against their UV absorbance was developed. Excellent regression coefficient (R2 = 0.994) was achieved from the linear calibration curve with 0.48 and 1.6 mg/L of LOD and LOQ, respectively. Results of the study clearly indicated that electrospun nanofibers obtained through PVDF could be used for an accurate determination of duloxetine hydrochloride. [ABSTRACT FROM AUTHOR]

This study evaluated the tensile strength of three aesthetic abutment materials at two different angulations (0 and 15°) to Ti-base and monolithic zirconia crowns. Prefabricated polyvinylidene difluoride (Medentika Implant) abutments were obtained and zirconia (Kingch) and polyetheretherketone (Ceramill) copings were manufactured using a computer-aided design/computer-aided manufacturing system (n = 12). Bonding surfaces of the copings and Ti-bases were air-abraded with alumina and then metal primer was applied. Self-adhesive resin cement (Multilink Hybrid Abutment) was used for cementation of copings to Ti-base. The bonding surfaces of the monolithic zirconia crowns (Upcera ST ML) were air-abraded and crowns were cemented using self-adhesive cement (seT PP). Data were analyzed using Kruskal–Wallis and Mann–Whitney U tests. No significant difference was found in the tensile strength of abutment to the crown interface for 0° tapered abutments (p > 0.05). Regarding 15° tapered abutments, the highest tensile strength values were obtained with zirconia abutments (p < 0.05). The tensile strength of monolithic zirconia crowns was lower than the restorations used in routine clinical practice. [ABSTRACT FROM AUTHOR]

Piezoelectric energy harvesting is the process of extracting electrical energy using energy harvester devices. Any stress in the piezoelectric material will generate induced voltage. Previous energy harvester device with stiff cantilever beam was generated low harvested energy. A flexural piezoelectric energy harvester is proposed to improve the generated harvesting energy. Polyvinylidene difluoride is a polymer piezoelectric material attached to a flexible circuit made of polyimide. Four interdigitated electrode circuits were designed and outsourced for fabrication. The polyvinylidene difluoride was then attached to the interdigitated electrode circuit, and a single clear adhesive tape was used to bind them. Four piezoelectric energy harvesters and ultrasonic ceramic generators were experimentally tested using a sieve shaker. The sieve shaker contains a two-speed oscillator, with M1=0.025 m/s and M2=0.05 m/s. It was used to oscillate the energy harvester devices. The resulting induced voltages were then measured. Design 4, with the widest width of electrode fingers and the widest gap between electrode fingers, had the highest power generated at an output load of 0.745 μW with the M2 oscillation speed. The oscillation speed of the sieve shaker impacted the energy harvester devices as a higher oscillation speed gave higher generated power. [ABSTRACT FROM AUTHOR]

Advanced glycation end products (AGEs) are formed through the reaction/modification of proteins by saccharides (e.g., glucose and fructose) and their intermediate/non-enzymatic products [e.g., methylglyoxal and glyceraldehyde (GA)]. In 2017, Dr. Takanobu Takata et al. developed the novel slot blot method to quantify intracellular GA-derived AGEs (GA-AGEs). Although the original method required nitrocellulose membranes, we hypothesized that the modified proteins contained in the AGEs may be effectively probed on polyvinylidene difluoride (PVDF) membranes. Because commercial lysis buffers are unsuitable for this purpose, Dr. Takata developed the slot blot method using an in-house-prepared lysis buffer containing 2-amino-2-hydromethyl-1,3-propanediol (Tris), urea, thiourea, and 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CHAPS) that effectively probes AGEs onto PVDF membranes. The slot blot method also entails the calculation of Tris, urea, thiourea, and CHAPS concentrations, as well as protein and mass to be probed onto the PVDF membranes. GA-AGE-modified bovine serum albumin (BSA, GA-AGEs-BSA) is used to draw a standard curve and perform neutralization against a non-specific combination of anti-GA-AGEs antibodies, thereby enabling the quantification of GA-AGEs in cell lysates. This paper presents the detailed protocol for slot blot analysis of intracellular GA-AGE levels in C2C12 cells. Key features • This protocol leverages the idea that advanced glycation end products are modified proteins. • The lysis buffer containing Tris, urea, thiourea, and CHAPS enables probing proteins onto PVDF membranes. • Intracellular GA-AGE levels may be quantified for some cell types using polyclonal anti-GA-AGE antibodies and standard GA-AGE-modified BSA. • The lysis buffer may be simultaneously prepared with the cell lysate. • There is no limit to the type of cultured cells used in the preparation of cell lysate., Competing Interests: Competing interestsThe authors declare no competing interests., (©Copyright : © 2024 The Authors; This is an open access article under the CC BY-NC license.)

In this study, several metal‐organic framework‐melamine foam columns were first developed and used as a laboratory‐made semi‐automatic solid phase extraction packed in syringe adsorber for the extraction of six triazine herbicides from vegetable oil samples coupled to high‐performance liquid chromatography‐tandem mass spectrometry. The metal‐organic framework‐foam columns were prepared using a simple approach by embedding the solid particles in melamine foam using polyvinylidene difluoride physical encapsulation. The method was applicable to a wide variety of metal‐organic framework materials, and the incorporated materials retained their unique properties. Key factors that affect the extraction efficiency, including the MIL‐101(Cr) amount, sample flow rate, type and volume of the eluting solvent, and flow rate of eluting solvent, were investigated. Under optimum conditions, the proposed method exhibited low limits of detection (0.017–0.096 ng/mL, S/N = 3) for six triazines. The relative standard deviations calculated for all herbicides ranged from 0.2 to 14.9%. This study demonstrated that the MIL‐101(Cr)‐foam column can be used as a high‐quality adsorption material for the detection of triazines in vegetable oils. [ABSTRACT FROM AUTHOR]

A polydopamine (PDA) layer was attached onto the surface of a polyvinylidene difluoride hollow fiber membrane via the self-polymerization of the dopamine. Amine-functionalized N-TiO2 (N-TiO2-NH2) nanoparticles were covalently bound with the PDA layer via amine-catechol adduct formation. N-TiO2 anchored onto the membrane surface could be activated by visible light irradiation, thus imparting the membrane’s self-cleaning activities. The coating method enhanced the contact area between photocatalytic particles and contaminants when compared to the membrane fabricated by the blending method. In comparison with ultraviolet (UV) light irradiation, the application of visible light irradiation could save energy and prevent membranes from deterioration. The membranes were characterized by scanning electron microscopy and their performances were evaluated based on the water permeability, humic acid (HA) rejection and antifouling property. Under visible light irradiation, the pure water flux of the membrane modified with (N-TiO2-NH2) (NTN) via dopamine could recover 100% of its original flux in the second day. The antifouling property of membranes modified with NTN could be further increased by UV irradiation; however, the UV light might deteriorate quickly the modified layer on the membrane surface. These results demonstrated that the methodology developed here was capable of preventing membrane fouling and cleaning the fouling surfaces. An important advantage using visible light irradiation is its relatively low energy costs and minimal deterioration of the membrane structure. [ABSTRACT FROM AUTHOR]

The addition of antibacterial material to hollow fiber membranes improves the membrane anti-biofouling characteristics. Antibacterial membranes were fabricated in this study to improve membrane function while also extending membrane lifetime. Neat polyvinylidene difluoride (PVDF) and PVDF hollow fiber membrane with the incorporation of antibacterial agent zinc oxide (ZnO) nanoparticles with various loading (2.5–7.5 wt.%) were fabricated by using dry/wet spinning method. The membrane structure, particle distribution, functional group, hydrophilicity, and pore size of each membrane were all assessed. The result shows that all ZnO/PVDF hollow fiber membranes have the asymmetric structure with even dispersion of ZnO nanoparticles throughout the membranes. The results showed that increased ZnO loadings considerably improved membrane hydrophilicity, and average pore size, in addition to good performance of pure water flux. Antibacterial testing shows that ZnO incorporated in the membrane matrix and membrane surfaces prevents bacteria that cause biofouling from adhering to the membrane. ZnO/PVDF membrane recorded excellent bovine serum albumin (BSA) rejection at 93.4% ± 0.4 with flux recovery rate at 70.9% ± 2.1. These results suggest that antibacterial ZnO/PVDF hollow fiber membranes are promising in relation to reducing biofouling for various water and wastewater treatment.

Recently, the demand for the recovery of valuable solutes from organic solvents/water mixtures has increased in various fields. Furthermore, due to the abundance of heat-sensitive valuable solutes, the demand for non-heated concentration technologies has increased. In this study, the direct contact membrane distillation (DCMD) using hydrophobic polyvinylidene difluoride (PVDF) hollow fiber membranes was investigated to confirm the possibility of recovering valuable solutes from organic solvents/water mixtures as a non-heated process. The DCMD with 1000 ppm NaCl aqueous solution achieved 0.8 kg/m2·h of vapor flux and >99.9% of NaCl retention, even at feed and coolant temperatures of 25 and 10 °C, respectively. Furthermore, when DCMD was conducted under various conditions, including feed temperatures of 25, 35 and 45 °C, and organic solvent concentration of 15, 30 and 50 wt%, using ethanol/water and acetonitrile/water mixtures containing 1000 ppm NaCl. A surfactant was also used as a valuable solute, in addition to NaCl. As a result, it was found that the total vapor flux increased with increasing temperature and concentration of organic solvents, as the partial vapor pressure of the organic solvents increased. Additionally, no solute leaked under any condition, even when the surfactant was used as a valuable solute.

This report demonstrates the fabrication of a composite hollow fiber membrane that efficiently recovers dissolved methane (dCH 4) from anaerobic wastewater treatment effluents via membrane contactor (MC) process. We first fabricated highly porous hollow fiber membranes (∼85% porosity) using polyvinylidene difluoride (PVDF). Then, we coated the whole structure (bulk), or lumen side of PVDF supports with polydimethylsiloxane (PDMS), a hydrophobic polymer possessing high gas permeability. The adjustment of the concentration of PDMS precursor mix could effectively serve for tuning the performance characteristics of MC membranes and helped suppress membrane wetting, a major performance-reducing factor. Despite their denser skin layers, the lumen-modified membranes demonstrated superior dCH 4 recovery flux. Mass transfer analyses have confirmed the importance of preserving bulk porosity while coating the membrane surfaces. The long-term performance tests performed using actual anaerobic effluents suggested that the PDMS coating did not accelerate fouling, such that the lumen-modified MC membranes showed an almost steady flux for 8 days with an anaerobic membrane bioreactor effluent. A high-strength effluent, obtained from an up-flow anaerobic sludge blanket reactor, induced faster fouling. However, we observed only a ∼20% flux decline in a 10-day operation. Thus, we propose that the designed PDMS-PVDF composite membranes are promising for industrial practices. Image 1 • We prepared PDMS-coated PVDF porous hollow fiber membranes for membrane contacting. • Both lumen- and bulk-modified PVDF membranes were successful in methane recovery. • Lumen-modified PDMS-PVDF membrane outperformed commercial PP and PDMS membranes. • Lumen-modified PVDF achieved long-term performance with actual anaerobic effluents. [ABSTRACT FROM AUTHOR]