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Stretchable dielectric polymer with high dielectric constant is a major component for electroluminescent devices. However, the intrinsic instability toward water severely limits their further applications in marine environment. Here, a transparent, underwater stable, and self‐healable dielectric material with high dielectric constant is reported. The electroluminescent device based on this newly designed fluoropolymer can work stably in aqueous conditions. There is no significant attenuation of mechanical and optoelectronic property after immersed in water and salty water for a month. The intrinsic self‐healing ability of the device makes it robust and resilient against unexpected minor or severe damages. [ABSTRACT FROM AUTHOR]

Three types of 9,9-bis(4-hydroxyphenyl)fluorene-based diols reacted with 4,4′-difluorobenzophenone via nucleophilic substitution polymerization to afford the corresponding aromatic poly(ether ketone)s. The resulting polyketones have excellent solubility in typical organic solvents, such as THF, CHCl3, and NMP. They also have good thermal stability above 400 °C (Td10). In particular, the surface tension of the polyketone, which has four C4F9 groups per repeating unit, is 18.7 mN/m, which is equal to that of PTFE. The introduction of propylene linkers and many C4F9 groups per repeating unit was effective at improving water/oil repellency. [ABSTRACT FROM AUTHOR]

Machine learning can be used to predict the properties of polymers and explore vast chemical spaces. However, the limited number of available experimental datasets hinders the enhancement of the predictive performance of a model. This study proposes a machine learning approach that leverages transfer learning and ensemble modeling to efficiently predict the glass transition temperature (Tg) of fluorinated polymers and guide the design of high Tg copolymers. Initially, the quantum machine 9 (QM9) dataset is employed for model pretraining, thus providing robust molecular representations for the subsequent fine‐tuning of a specialized copolymer dataset. Ensemble modeling is used to further enhance prediction robustness and reliability, effectively addressing the problems owing to the limited and unevenly distributed nature of the copolymer dataset. Finally, a fine‐tuned ensemble model is used to navigate a vast chemical space comprising 61 monomers and identify promising candidates for high Tg fluorinated polymers. The model predicts 247 entries capable of achieving a Tg over 390 K, of which 14 are experimentally validated. This study demonstrates the potential of machine learning in material design and discovery, highlighting the effectiveness of transfer learning and ensemble modeling strategies for overcoming the challenges posed by small datasets in complex copolymer systems. [ABSTRACT FROM AUTHOR]

The development of self‐healing materials is an effective strategy to improve the service life of polymer materials. In this study, self‐healing waterborne fluorinated polyurethane‐acrylate (WFPUA) containing UV‐responsive coumarin groups was prepared by Pickering emulsion polymerization using modified cellulose nanocrystal as a stabilizer. The effect of double bond‐terminated waterborne polyurethane content on emulsion polymerization and latex film properties was mainly studied. Due to the dynamic reversibility of the coumarin groups and the synergistic effect of hydrogen bonds, the optimized sample (WFPUA‐30) had excellent mechanical properties and self‐healing properties. The tensile strength was 5.24 MPa and the elongation at break was 267%. The self‐healing efficiency of tensile strength and elongation at break after 6 h of repair was 86.52% and 93.20%, respectively. In addition, due to the presence of fluorine‐containing groups, the water and oil contact angles of the latex film could reach 101.7° and 82.1°, respectively. This work broadens the way for the manufacture of self‐healing and multifunctional waterborne polyurethane‐acrylates. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Among electroactive polymers, polyvinylidene fluorine (PVDF) and its copolymers present the highest piezoelectric response which makes them very attractive for applications combining flexibility and piezoelectricity. The use of composites with the incorporation of electroactive ceramics (with a very high piezoelectric coefficient compared to polymers) into the fluorinated polymer matrix allows for an increase in the material piezoelectric response while keeping ductility. The review presents in the first part an overview of the impact of the ceramic particle size and dimension and the filler content. In ceramic/polymer composites, the interface between both constituents is generally weak and has to be strengthened. This review summarizes in the second part different strategies used to improve the interface between the electroactive fillers and the piezoelectric fluorinated polymer matrix to increase the piezoelectric performance of composites. Molecular coupling agents (CAs) are presented and polymer‐based CAs synthesized from "grafting to" and "grafting from" techniques are described. In the last part, the combination of antiparallel poling of ceramic and polymer piezoelectric responses is reported in the composites and the potential of such materials for future development is finally discussed. Highlights: Piezoelectric properties of composites with electroactive ceramic fillers in fluorinated polymer matrix are discussed.Different strategies used to improve the interface between electroactive fillers and piezoelectric fluorinated polymer matrix are presented.The synthesis of molecular CAs or polymer‐based CAs from "grafting to" or "grafting from" techniques is described.The piezoelectric response of ceramic/polymer composites poled in parallel and anti‐parallel are summarized.The antiparallel poling of electroactive ceramic and piezoelectric polymer contributions is a promising way to maximize piezoelectric performances. [ABSTRACT FROM AUTHOR]

Metabolic reprogramming is a key characteristics of tumor cells, mainly manifested by abnormal metabolism and tumor hypoxia. Here, the design of PolyFBODIPY characterized by the presence of BODIPY photosensitizers, fluorinated aliphatic chains as Oxygen affinity materials, and reactive oxygen species‐sensitive thioketal linkers is reported. PolyFBODIPY subsequently self‐assembles into NP@PolyFBODIPY which is capable of delivering oxygen and photosensitizers simultaneously and generating ROS under light irradiation, resulting in rapid polymer degradation and nanoparticle dissociation via breaking ROS‐sensitive thiol ketal linkers. NP@PolyFBODIPY can target hypoxic tumor plasticity to reprogram metabolism for recapturing photodynamic‐immunotherapy sensitivity for completely inhibiting tumor growth on multi‐drug‐resistant patient‐derived lung cancer xenografts (PDXMDR). Moreover, NP@PolyFBODIPY‐mediated photodynamic‐immunotherapy activates antitumor immune responses and effectively inhibits tumor growth and lung metastasis on an orthotropic metastatic triple‐negative breast cancer model. Mechanistically, metabolomics and lipidomics analysis reveals that NP@PolyFBODIPY‐mediated photodynamic‐immunotherapy not only destroys the redox state of cancer cells, but also affects the metabolism of lipid, amino acid, and d‐glutamine, thereby finally promoting autophagy and apoptosis and inhibiting the proliferation of cancer cells. These results highlight the potential of clinical translation of NP@PolyFBODIPY in targeting hypoxic tumor plasticity via oxygen supply, which reprograms the cellular metabolism for recapturing photodynamic‐immunotherapy sensitivity. [ABSTRACT FROM AUTHOR]

Sulfur is one of the most abundant and economical elements in the p‐block family and highly redox active, potentially utilizable as a charge‐storing electrode with high theoretical capacities. However, its inherent good solubility in many electrolytes inhibits its accessibility as an electrode material in typical metal‐sulfur batteries. In this work, the synthetically designed fluorinated porous polymer, when treated with elemental sulfur through a well‐known nucleophilic aromatic substitution mechanism (SNAr), allows for the covalent integration of polysulfides into a highly conjugated benzimidazole polymer by replacing the fluorine atoms. Chemically robust benzimidazole linkages allow such harsh post‐synthetic treatment and facilitate the electronic activation of the anchored polysulfides for redox reactions under applied potential. The electrode amalgamated with sulfurized polymer mitigates the so‐called polysulfide shuttle effect in the lithium‐sulfur (Li−S) battery and also enables a reversible, more environmentally friendly, and more economical aluminum‐sulfur (Al−S) battery that is configured with mostly p‐block elements as cathode, anode, and electrolytes. The improved cycling stabilities and reduction of the overpotential in both cases pave the way for future sustainable energy storage solutions. [ABSTRACT FROM AUTHOR]

The current increase in the use of photovoltaic (PV) energy demands the search for solutions to recycle end-of-life modules. This study evaluated the use of a mechanical pre-treatment in the thermal recycling of c-Si crystalline PV modules, which were submitted to recycling routes to separate and concentrate the materials of interest. The first route was constituted by only thermal treatment, and the second route was constituted by a mechanical pre-treatment to remove the polymers from the backsheet, and subsequent thermal treatment. The exclusively thermal route was performed at 500°C, varying dwell times between 30 and 120 minutes in the furnace. In this route, the best results were obtained in 90 minutes, with a maximum degradation of 68% of the polymeric mass. In route 2, a micro-grinder rotary tool was used to remove the polymers from the backsheet and, subsequently, thermal treatment performed at 500°C, with dwell times in the furnace ranging between 5 and 30 minutes. The mechanical pre-treatment removed about 10.32 ± 0.92% of the mass of the laminate PV module. By this route, only 20 minutes of thermal treatment were needed for the total decomposition of the polymers, that is, a reduction of 78% in the oven time. With route 2, it was possible to obtain a concentrate with 30 times more silver than the PV laminate and 40 times more than a high-concentration ore. Furthermore, with route 2 it was possible to reduce the environmental impact of heat treatment and energy consumption. Graphical Abstract [ABSTRACT FROM AUTHOR]

A dissolved oxygen sensor was developed based on time‐domain lifetime measurement with an oxygen sensing film. The oxygen sensing film was fabricated by embedding PtOEP in a highly stable and highly hydrophobic fluorinated matrix synthesized from methacrylate, fluorinated methacrylate, and 3‐(tris(trimethylsilyloxy)silyl)propyl methacrylate via free radical polymerization. The fluorinated methacrylate provided the high stability and the 3‐(tris(trimethylsilyloxy)silyl)propyl methacrylate provided the extra hydrophobicity. The PtOEP was excited using pulsed signals from a green‐light LED and the fluorescence lifetime was evaluated by time‐domain lifetime measurement. The dynamical quenching of fluorescence response by dissolved oxygen was calibrated using the Stern‐Volmer plot with a high τ0/τ100 ratio of 5.68 and a Stern‐Volmer constant of 0.112 mg−1 dm3. It was demonstrated that the dissolved oxygen sensing film showed high stability under the varied excitation intensity and long‐term stability in the accelerated aging experiment and the repeated freeze‐thaw‐cycling tests. [ABSTRACT FROM AUTHOR]

The synthesis of transparent fluorinated polystyrene siloxanes with good thermostability and dielectric properties. [Display omitted] • Three silicone monomers were prepared by Piers-Rubinsztajn reaction. • The obtained polystyrene siloxanes exhibit good and stable dielectric properties. • All polystyrene siloxanes show high thermostability and good transparency. Three silicone monomers were prepared by Piers-Rubinsztajn reaction which catalyzed condensation reaction of hydrosilane and alkoxysilane under mild conditions. Due to the thermo-crosslink reaction of styrene groups with vinyl of siloxane, the obtained polystyrene siloxanes (P1 - P3) showed high thermostability with the 5 % weight loss temperature (T 5d) of above 440 °C and the residue at 1000 °C of over 40 %. Thanks to the introduce of trifluoromethyl with large free volume, P3 exhibited low dielectric constant (D k) of 2.45 and ultralow dielectric loss (D f) of 3.41 × 10−3 at high frequency of 10 GHz. Meanwhile, P1 - P3 remained stable dielectric properties after being soaked in boiling water for 72 h. In particularly, all polymers exhibited good transparency with transmittance of 90% varying from 500 nm to 1000 nm. These materials can meet the requirements of matrix materials or packaging resins used in high-frequency communication equipment. [ABSTRACT FROM AUTHOR]

Nanoparticles have recently emerged as valuable tools in biomedical imaging techniques. Here PEGylated and fluorinated nanocapsules based on poly(3-hydroxyalkanoate) containing a liquid core of perfluorooctyl bromide PFOB were formulated by an emulsion-evaporation process as potential 19F MRI imaging agents. Unsaturated poly(hydroxyalkanoate), PHAU, was produced by marine bacteria using coprah oil and undecenoic acid as substrates. PHA-g-(F; PEG) was prepared by two successive controlled thiol-ene reactions from PHAU with firstly three fluorinated thiols having from 3 up to 17 fluorine atoms and secondly with PEG-SH. The resulting PHA-g-(F; PEG)-based PFOB nanocapsules, with a diameter close to 250-300 nm, are shown to be visible in 19F MRI with an acquisition time of 15 min. The results showed that PFOB-nanocapsules based on PHA-g-(F; PEG) have the potential to be used as novel contrast agents for 19F MRI. [ABSTRACT FROM AUTHOR]

[Display omitted] • P(VDF-TRFE) boosts Spiro-OMeTAD-based power conversion efficiency (PCE) to 24.1%. • P(VDF-TRFE)-integrated cells retain > 90 % PCE for 45 days under ambient conditions. • P(VDF-TRFE)-integrated cells retained 94% PCE after 1080-hour light-soaking. • Robust bonding between P(VDF-TRFE) and Li-TFSI/TBP enhances HTL film quality. This study demonstrates the transformative impact of incorporating poly(vinylidene fluoride-co-trifluoroethylene) P(VDF-TRFE) as an additive in the hole transport layer (HTL) of 2,2′,7,7′-Tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (Spiro-OMeTAD). The P(VDF-TRFE) additive forms resilient coordination bonds with 4- tert -butylpyridine (TBP) and lithium bis(trifluoromethanesulfonyl)imide additives, which mitigates TBP evaporation and improves Spiro-OMeTAD film quality. In addition, we observed improvements in solar cell current–voltage characteristics consistent with increased Spiro-OMeTAD conductivity and suppressed non-radiative recombination at the HTL/perovskite interface. P(VDF-TRFE)-integrated devices exhibit an increment in power conversion efficiency (PCE) up to 24.1 % (reverse scan) from a reference PCE of 21.4 %. Furthermore, the unencapsulated P(VDF-TRFE)-integrated devices demonstrate improved stability, retaining over 90 % PCE after 45 days in an ambient atmosphere in the dark and 94 % PCE after 1080 h of continuous light-soaking in a nitrogen environment. This work demonstrates how additive engineering, as exemplified by P(VDF-TRFE), can effectively address stability and performance challenges within Spiro-OMeTAD in perovskite solar cells. [ABSTRACT FROM AUTHOR]

Charge trap in amorphous perfluoro-polymer electret is studied, focusing on electron trap site and trap energy. Low-energy inverse photoelectron spectroscopy is adopted to measure solid-state electron affinity (EA) of cyclic transparent optical polymer (CYTOP). EA of CYTOP CTL-S is discovered by compensating the unwanted charge-up effect. Negatively-charged electret materials (polyethylene, ethylene-tetra-fluoro-ethylene, poly-tetra-fluoro-ethylene, and CYTOP) are analyzed by quantum mechanical calculation. Density functional theory with long-range correction is adopted to analyze orbital energies of single molecular systems. Intramolecular distribution of trapped electron and EA are investigated. Calculated electron affinities of CYTOP polymers with different end group are qualitatively in accordance with trapped charge stability measured with thermal stimulated discharge, signifying that electron affinities obtained with the present simulation can be used as an index of amorphous polymer electret.

As the hydrogen market is projected to grow in the next decades, the development of more efficient and better-performing polymer electrolyte membrane fuel cells (PEMFCs) is certainly needed. Water management is one of the main issues faced by these devices and is strictly related to the employment of fluorinated materials in the gas diffusion medium (GDM). Fluorine-based polymers are added as hydrophobic agents for gas diffusion layers (GDL) or in the ink composition of microporous layers (MPL), with the goal of reducing the risk of membrane dehydration and cell flooding. In this review, the state of the art of fluorinated polymers for fuel cells is presented. The most common ones are polytetrafluoroethylene (PTFE) and fluorinated ethylene propylene (FEP), however, other compounds such as PFA, PVDF, PFPE, and CF4 have been studied and reported. The effects of these materials on device performances are analyzed and described. Particular attention is dedicated to the influence of polymer content on the variation of the fuel cell component properties, namely conductivity, durability, hydrophobicity, and porosity, and on the PEMFC behavior at different current densities and under multiple operating conditions.

We synthesized pyrene-containing amphiphilic fluorinated copolymers p(C7F15MAA/PyMMA)s through free radical polymerization. The pyrene composition ratio was readily tuned from 0.6 to 3 mol% with different monomer feeding ratios, designated as p(C7F15MAA/PyMMA0.6) and p(C7F15MAA/PyMMA3). p(C7F15MAA/PyMMA) nanoparticle films were prepared by dropcasting copolymer solutions onto substrates with the mixture of AK-225 and acetic acid. The copolymer nanoparticle film surfaces exhibited superhydrophobic character with a water contact angle of greater than 160° and low surface free energy (< 19 mN m−1). The emission from the p(C7F15MAA/PyMMA0.6) nanoparticle film was dominated with monomeric emission, while that from the p(C7F15MAA/PyMMA3) nanoparticle film showed mainly excimer emission. The dissolved oxygen sensing performance of the nanoparticle films was also investigated in terms of the different emission modes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimization of dehydrofluorination of poly(vinylidene fluoride), PVDF. • The α-phase of PVDF involved in dehydrofluorination and transforms into the more electroactive β-phase. • The tail-to-tail addition of PVDF is not disturbed during dehydrofluorination. • 1H-19F heteronuclear correlation spectroscopy (Hetero COSY) evidences the formation of the –(CH=CF)– double bond. • Detailed mechanistic insights of dehydrofluorination evidences some crosslinking. This study presents newer insights on the dehydrofluorination of poly(vinylidene fluoride), PVDF, in alcoholic sodium hydroxide using infrared (IR), Raman and nuclear magnetic resonance (1H and 1H {19F}) spectroscopies. Details on the reactivity of phases and site selectivity of different orientations viz head-to-tail and tail-to-tail is comprehensively examined using IR/Raman and NMR (1D and 2D), respectively. The α-phase is prominently involved in dehydrofluorination and transforms into the more electroactive β-phase. 1H NMR spectra highlight that the tail-to-tail addition of PVDF is not disturbed and remains unaffected during dehydrofluorination reaction. Furthermore, 1H-19F heteronuclear correlation spectroscopy (Hetero COSY) clearly evidences the formation of the –(CH=CF)– double bond in dehydrofluorinated PVDF. Moreover, detailed mechanistic insights of dehydrofluorination reaction and possible internal crosslinking during the chemical transformation is presented. [ABSTRACT FROM AUTHOR]

• Two D-π-A-π-D type polymer precursors based on fluorinated benzothiadiazole acceptor unit with thiophene and EDOT as donor units were synthesized. • Types of donor units caused outstanding effects on the photophysical properties of the fluorinated precursors and its polymers. • The precursors F-EDOT exhibited lower onset oxidation potentials than F-Th. • The lower band gap P(F-EDOT) polymers shown favorable redox activity and better redox stability. • The stable green P(F-EDOT) has more satisfied electrochromic properties than P(F-Th). In this work, two fluorinated D-π-A-π-D type electrochromic polymer precursors were synthesized by Stille coupling reactions that using mono-fluorine atom substituted benzothiadiazole (F-BT) as acceptor units (A), 3-dodecylthiophene as the π-bridge, and thiophene (Th) and 3,4-ethoxylenedioxythiophene (EDOT) as donor units (D), respectively, and their optical properties were characterized by various analytical techniques. All of them were electropolymerized into the corresponding fluorinated electrochromic polymer films (P(F-Th) and P(F-EDOT)). F-EDOT has red-shifted absorption spectra and emission spectra but with relatively lower fluorescence quantum yield, which is due to the strong electron donating ability of EDTO unit. The lower oxidation potential of F-EDOT (0.72 V) is very beneficial to improve the optoelectronic properties of its electropolymerized P(F-EDOT) with favorable redox activity and better redox stability (remained 73 % redox activity after 1000 cycles). Due to the enhanced π-π* conjugation effect, P(F-EDOT) has shown a red-shifted absorption spectra compared to P(F-Th) and a decreased optical band gap (1.6 eV for P(F-Th); 1.38 eV for P(F-EDOT)). Although P(F-Th) has a higher coloration efficiency (370.4 cm2C−1 at 894 nm) and faster response time (0.04–0.37 s), the transparent green P(F-EDOT) should have more satisfied electrochromic properties due to its favorable coloration efficiency (192 cm2C−1 at 458 nm), higher optical contrast (20.6 % at 458 nm), and also very fast response time (0.2–0.86 s), especially the enhanced optical stability and better memory effect. Overall, these properties highlight the potential applications of the current fluorinated D-π-A-π-D type polymers in displays and smart windows. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanoparticles have recently emerged as valuable tools in biomedical imaging techniques. Here PEGylated and fluorinated nanocapsules based on poly(3-hydroxyalkanoate) containing a liquid core of perfluorooctyl bromide PFOB were formulated by an emulsion-evaporation process as potential 19F MRI imaging agents. Unsaturated poly(hydroxyalkanoate), PHAU, was produced by marine bacteria using coprah oil and undecenoic acid as substrates. PHA-g-(F; PEG) was prepared by two successive controlled thiol-ene reactions from PHAU with firstly three fluorinated thiols having from 3 up to 17 fluorine atoms and secondly with PEG-SH. The resulting PHA-g-(F; PEG)-based PFOB nanocapsules, with a diameter close to 250–300 nm, are shown to be visible in 19F MRI with an acquisition time of 15 min. The results showed that PFOB-nanocapsules based on PHA-g-(F; PEG) have the potential to be used as novel contrast agents for 19F MRI.

High-dielectric constant (κ) materials have been extensively investigated for several potential applications, particularly in low-voltage-operating organic field-effect transistors (OFETs). To ensure the operational stability of the OFET, the interface between the organic semiconductor and the high- κ dielectric should be fully controlled. In the current work, we overcoated a fluorinated polymer, namely poly(pentafluorostyrene) (PFS), onto one of the high- κ materials, namely barium titanate (BaTiO 3), and used this bilayer to fabricate highly stable OFETs. The surfaces of the BaTiO 3 dielectric layers were effectively modified with the PFS overcoating. Compared to the uncoated BaTiO 3 , the PFS/BaTiO 3 bilayer dielectric showed significantly reduced leakage current and altered surface properties. The smoothness of the surfaces of the PFS/BaTiO 3 films appeared to have been responsible for the observed improved crystal structures of the overlying pentacene molecules. In addition, the surface dipoles and electron-withdrawing character of the PFS/BaTiO 3 films built a high hole injection barrier between the semiconductor and dielectric layers, with this barrier blocking hole trapping. Finally, overcoating BaTiO 3 with PFS allowed the resulting PFS/BaTiO 3 to be utilized as a gate dielectric layer for highly stable OFETs during low-voltage operation. These OFETs exhibited hysteresis-free transistor performances and reliable operation under a sustained gate-bias stress in air. • Fluorinated polymer was overcoated on high- κ BaTiO 3 dielectric film. • Overcoating of the fluorinated polymer allowed BaTiO 3 film to exhibit good surface morphologies, insulating properties. • The OFETs prepared with fluorinated polymer/BaTiO 3 dielectric film improved reliable performances under gate-bias stress. [ABSTRACT FROM AUTHOR]

We study the surface morphology, mass loss and wetting of fluorinated ethylene propylene surfaces which have been treated using reactive ion etching. We find that etching with argon gas alone results in a network structure, while oxygen combined with argon results in pyramidal hair-like structures, and by adding CF 4 globules are found. We demonstrate that small alterations in the preparation allows one to create samples with either homogeneous nanostructures exhibiting large contact angles and very low hysteresis or more irregular structures which exhibits pinning sites that allow very large contact angle hysteresis. The advancing and receding contact angles are estimated based on the tilting plate method, and the pinning force measured for the samples is investigated for large droplets. The results reported here indicate that surface structure and contact angle hysteresis of fluorinated polymers can be manipulated for applications where either large or small contact angle hysteresis is needed. [ABSTRACT FROM AUTHOR]

Solution-processed polymer semiconductors are key materials in the fabrication of lightweight, low-cost, and flexible electronic devices without using the high-vacuum process. For practical applications, reliable device operations based on these materials are required. In this study, we propose a strategy to improve the operation stability of organic field-effect transistors (OFETs) using solution-processed polymer semiconductor/insulator blends as the active channel prepared by introducing a fluorinated insulating polymer in the blends. The semiconducting polymer forms nanowire networks in spin-coated ternary blend films, which serve as charge transport pathways in the insulating polymer matrix consisting of the fluorinated polymer and polystyrene. Owing to its high surface potential attributed to the strongly electron-withdrawing structure, the fluorinated polymer provides a large energy barrier for suppression of the hole trapping at the semiconductor/insulator interface. Consequently, OFETs based on the ternary blend films with an optimized polymer composition exhibit almost hysteresis-free transfer and output characteristics and superior electrical stabilities under sustained gate-bias stresses in both N 2 and air atmospheres. We believe that our study provides a practical route to the fabrication of OFETs based on polymer semiconductor/insulator blend systems with high operation stabilities. Unlabelled Image • A fluorinated polymer PFS was introduced in semiconductor/insulator ternary blends. • P3HT formed nanowire networks in the blend films and acted as charge transport pathways. • PFS induced a large energy barrier for suppression of the hole trapping at interfaces. • The OFETs using the blend film as the active layer exhibited superior gate-bias stabilities. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has attracted growing attention in the field of cancer therapy due to its non-invasive intervention and initiation of antitumor immune responses by use of non-toxic photosensitizers (PS) and topical light irradiation. However, inherent hypoxia and immunosuppression mediated by checkpoints in tumors severally impair the efficacy of PDT and PDT-induced immunity. Herein, a multi-functional nanoplatform is rationally constructed by fluorinated polymer nanoparticle saturated with oxygen in advance, which simultaneously encapsulated PS (Ce6) and an indoleamine 2,3-dioxygenase (IDO) inhibitor (NLG919). In particular, the tumor hypoxic microenvironment is obviously relieved and much more reactive oxygen species (ROS) is generated by fluorinated nanoparticle compared with alkylated polymer nanoparticle as a control in vitro and in vivo , this is mainly because the fluorinated polymers are endowed with high oxygen carrying capacity which also contributed to the relief of hypoxia. Meanwhile, compared to PDT alone, the co-encapsulation of IDO inhibitor and PS can further greatly enhance efficacy for inhibiting the growth of primary and abscopal tumors via enhanced T cell infiltration. This study can provide a convenient and practical strategy for enhancing the therapeutic effect of PDT and relieving immune suppression, in turn affording clinical benefits for cancer treatment. [ABSTRACT FROM AUTHOR]

A series of novel fluorinated polyacrylic acrylate oligomers with different fluorine contents were successfully prepared by acid–epoxy reaction between acrylic acid and a glycidyl methacrylate (GMA)-functional acrylic copolymer, which was presynthesized by traditional free radical polymerization in solvent with ethyl methacrylate, n-butyl acrylate, dodecafluoroheptyl methacrylate, and GMA. The UV-curable coatings were prepared with various amounts of the obtained fluorinated polyacrylic acrylate oligomer. The influences of fluorine content on the properties of UV-curable films were investigated by the tests of hydrophobicity, oleophobicity, thermal stability, water absorption, hardness, and chemical resistance. The results showed that the water contact angle of cured films increased from 78.5° to 104.5°, n-hexadecane contact angles increased from 12.3° to 43.4°, the water absorption decreased from 1.27% to 0.63%, while the fluorine content of the cured films increased from 0 to 5.7 wt%. In addition, thermal stability and chemical resistance of the curable films containing fluorinated oligomer were also clearly improved. [ABSTRACT FROM AUTHOR]

Abstract We demonstrate electrophoresis of non-ionic poly(methacrylate)s containing pendant fluoroalkanes for developing a new polymeric system of enhanced electrophoretic deposition (EPD) by making use of the high electronegativity of fluorinated fragments. Three kinds of fluorinated poly(methacrylaes)s with various fluorine content and molecular weights are synthesized via reversible addition-fragmentation chain transfer (RAFT) radical polymerization. These polymers are characterized in the assembled dispersion particle states in the mixture solvents of tetrahydrofuran and several kinds of alcohols, and investigated for their EPD coating capability onto several kinds of metal plates. In addition, the coatings of fluorinated-polymers prepared via EPD are characterized by performing contact angle measurements. The results reveal exciting electrophoretic behavior of the simple fluorinated poly(methacrylate)s, and we propose the probable EPD mechanism based on our findings. This will lead to expansion of availability of non-ionic polymers with the instinctive EPD function, which gives insights into a new manipulation technique of functional coating. Graphical abstract Image 1 Highlights • The first example of electrophoretic non-ionic fluorinated polymethacrylates. • The electrophoretic behaviors were dependent on the sovlents and metals. • Electrophoretic deposition (EPD) provided the deposited surface, which showed low surface energy. [ABSTRACT FROM AUTHOR]

Charge trap in amorphous perfluoro-polymer electret is studied, focusing on electron trap site and trap energy. Low-energy inverse photoelectron spectroscopy is adopted to measure solid-state electron affinity (EA) of cyclic transparent optical polymer (CYTOP). EA of CYTOP CTL-S is discovered by compensating the unwanted charge-up effect. Negatively-charged electret materials (polyethylene, ethylene-tetra-fluoro-ethylene, poly-tetra-fluoro-ethylene, and CYTOP) are analyzed by quantum mechanical calculation. Density functional theory with long-range correction is adopted to analyze orbital energies of single molecular systems. Intramolecular distribution of trapped electron and EA are investigated. Calculated electron affinities of CYTOP polymers with different end group are qualitatively in accordance with trapped charge stability measured with thermal stimulated discharge, signifying that electron affinities obtained with the present simulation can be used as an index of amorphous polymer electret. [ABSTRACT FROM AUTHOR]

Abstract The aim of this work is to correlate the presence of the pending -CF 3 group on the microstructure and the relaxation behavior of the amorphous phase in a fluorinated terpolymer. On this basis, the properties of EFEP (ethylene-tetrafluoroethylene-hexafluoropropylene) are compared to those of ETFE (ethylene-tetrafluoroethylene). For both polymers, the lower hydrophobic character compared to PTFE (polytetrafluoroethylene) is related to the modification of the fluorine sheet-like orientation. Besides, it is noticed that the–CF 3 groups create defects in the crystalline phase and thus, decrease the melting temperature and degree of crystallinity in EFEP compared to ETFE. Moreover, the steepness of the main relaxation time evolution with temperature and associated to the amorphous phase is clearly modified. Once again the steric hindrance of –CF 3 groups decreases the packing efficiency in EFEP compared to the fluorinated polymers without pending groups. Graphical abstract Image 1 Highlights • Pending fluorinated groups modify the crystalline/amorphous arrangements. • High ability to crystallize was evidenced for the studied materials. • Thermal signature of amorphous phase was only revealed after thermal annealing. • Main relaxation process was significantly affected by the voluminous pending group. [ABSTRACT FROM AUTHOR]

Abstract Fluorinated polymers have been widely used in triboelectric sensors, displays, and energy harvesting devices because of their superior electron affinity, which leads to the negative triboelectric materials. While previous reports have shown that the control of dielectric constants of fluorinated polymers can increase the triboelectric output performance, the exact relationship between the molecular structures of fluorinated polymers and the resulting triboelectric properties is still elusive. In this study, we demonstrate that the molecular chain structures of the fluorinated polymers depending on the number of fluorine units, the molecular weight (M w), and conditions such as spin rate and annealing temperature directly affect the relative dielectric constants of dielectric layers and the triboelectric polarity, which are closely related to the triboelectric output performance. We observe that the polymer chain packing structures result in the increase of the relative dielectric constants, thus leading to the improvement of triboelectric output currents. Among the fluorinated polymers used in this study, a poly (2,2,2-trifluoroethyl methacrylate) polymer with three fluorine units and M w of ~ 20 kg/mol shows the best triboelectric output performance. Our molecular engineering strategy to control the dielectric constants of fluorinated polymers can be a robust platform for the fundamental studies of triboelectric materials and their applications in diverse energy harvesting and sensing devices. Graphical abstract We present the molecular structure engineering of fluorinated dielectric polymer for enhancement of triboelectric performance, which depends on different number of fluorine units, molecular weight, and process condition. The molecular packing structure affects the change of surface potential as well as the free volume in the polymer matrix, resulting in the control of dielectric constant and final triboelectric performances. Our molecular engineering strategy can be a feasible method to modify the triboelectric output performance and can be extended into diverse energy harvesting and sensing devices. fx1 Highlights • Synthesized fluorinated polymer with different fluorine chain for the triboelectric properties. • Demonstrated correlation between polymer chain structures and relative dielectric constants. • Tuning the dielectric constants can control the triboelectric output performances. [ABSTRACT FROM AUTHOR]

In this study, we present the surface patterning of a biopolymer poly(l-lactide) (PLLA) for fibroblast growth enhancement. The patterning is based on a self-organized pore arrangement directly fabricated from a ternary system of a solvent-nonsolvent biopolymer. We successfully created a porous honeycomb-like pattern (HCP) on a thermally resistant polymer—fluorinated ethylene propylene (FEP). An important preparation step for HCP is activation of the substrate in Ar plasma discharge. The polymer activation leads to changes in the surface chemistry, which corresponds to an increase in the substrate surface wettability. The aim of this study was to evaluate the influence of the PLLA concentration in solution on the surface morphology, roughness, wettability, and chemistry, and subsequently, also on fibroblast proliferation. We confirmed that the amount of PLLA in solution significantly affects the material surface properties. The pore size of the prepared layers, the surface wettability, and the surface oxygen content increased with an increasing amount of biopolymer in the coating solution. The optimal amount was 1 g of PLLA, which resulted in the highest number of cells after 6 days from seeding; however, all three biopolymer concentrations exhibited significantly better results compared to pristine FEP. The cytocompatibility tests showed that the HCP promoted the attachment of cell filopodia to the underlying substrate and, thus, significantly improved the cell–material interactions. We prepared a honeycomb biodegradable support for enhanced cell growth, so the surface properties of perfluoroethylenepropylene were significantly enhanced.

Fluorinated (F6) and zwitterionic, as well as phosphorylcholine (MPC) and sulfobetaine (MSA), copolymers containing a low amount (1 and 5 mol%) of 3-(trimethoxysilyl)propyl methacrylate (PTMSi) were prepared and covalently grafted to glass slides by using the trimethoxysilyl groups as anchorage points. Glass-surface functionalization and polymer-film stability upon immersion in water were proven by contact angle and angle-resolved X-ray photoelectron spectroscopy (AR-XPS) measurements. Antifouling performance of the grafted films was assayed against the yeast Candida albicans, the most common Candida species, which causes over 80% of candidiasis. Results revealed that the F6 fluorinated, hydrophobic copolymers performed much better in reducing the adhesion of C. albicans, with respect to both corresponding zwitterionic, hydrophilic MPC and MSA counterparts, and were similar to the glass negative control, which is well-known to inhibit the adhesion of C. albicans. A composition-dependent activity was also found, with the films of copolymer with 99 mol% F6 fluorinated co-units performing best.

Learning the micro-mechanisms of fluorinated polymers during mechanical response is more difficult than that of common polymers due to the unique intrinsic characteristics of the fluorine element. In this paper, we applied molecular dynamics simulations to study deformation mechanisms of poly(vinylidine fluoride-co-chlorotrifluoroethylene) during uniaxial tension. We analyzed the variations of individual energy components and structural distribution curves versus strain in addition to the commonly used stress-strain curves and microstructure evolutions during stretching. The elastic limit is ɛ = 0.02, ɛ = 0.06 is the yield point, ɛ = 0.24 is the termination of the softening, necking occurs at 0.24 < ɛ < 0.5, strain hardening occurs at 0.5 < ɛ < 2.6, and ɛ = 2.6 is the damage or brake point. The elastic behavior of the material does not rely on strain rate, the obvious effect of strain rate can be seen at the yield region and strain softening region, and the stress values are not influenced by strain rates at the softening and hardening stages. Overall, total potential energy is mainly correlated with non-bonded energy, and the proportion of ΔE overwhelms all the others. The energy components are ordered: ΔE > ΔE > > ΔE > ΔE > ΔE. The chain conformation at yield point is almost unchanged compared with the pre-stretching conformation. The chain conformations at the end of strain softening changes more obviously than that at yield point. The molecular chains maintain random coil structure before strain hardening, and switch into a stretch chain conformation gradually during strain hardening. The maximum change in bond angle during the stretching process is F-C-H, the largest change in bond length is the C-Cl bond, and the largest change in dihedral angle is H-C-C-H. The change of non-bonded interaction in the poly(VDF-co-CTFE) system is much larger than the bonding interaction, and the main factor affecting bonding interaction is the change of angles. [ABSTRACT FROM AUTHOR]

A novel polymerizable fluorocarbon surfactant, perfluoro (4-methyl-3, 6-dioxaoct-7-ene) sodium sulfonate (PSVNa), was synthesized and characterized. The fluorocarbon surfactant PSVNa and its mixture PSVNa/SDS were used as emulsifiers during the emulsion polymerization of DFHMA/MMA. The investigation of polymerization kinetics, particle size, and stability of the emulsions revealed that PSVNa has excellent emulsifying properties. The NMR spectrum of the copolymer and the detection of residual PSVNa show that more than 95% of the fluorocarbon surfactants have been linked to the polymer chains by radical polymerization, which will greatly reduce the environmental pollution caused by fluorinated surfactants. [ABSTRACT FROM AUTHOR]

To effectively modulate the molecular energy levels of isoindigo-based polymers through side-chain modification on the donor segments, three alkoxyphenyl-modified benzo[1,2-b:4,5-b′]dithiophene (BDT) were synthesized and used as electronic-donor units, which were copolymerized with the electron-withdrawing segment 2-ethylhexyl-substituted isoindigo (IID) to construct donor-acceptor (D-A) polymers. The obtained three polymers are named as P-IID , m F-IID and o F-IID , which possess 4-(2-octyldodecaneoxy)-phenyl, 2-fluoro-4-(2-octyldodecaneoxy)-phenyl and 3-fluoro-4-(2-octyldodecaneoxy)-phenyl side-chains in the BDT unit, respectively. All polymers display broad absorption regions with the film absorption edges of 759 nm ( P-IID ), 742 nm ( m F-IID ) and 726 nm ( o F-IID ). The fluorination on the phenyl side-chains of BDT unit results in obvious blue-shift in the absorption spectra, especially for the ortho -position fluorinated polymer o F-IID because of the enlarged dihedral angles between the phenyl rings and the BDT backbones. Gradient reduction in the highest occupied molecular orbital (HOMO) energy levels are observed for the three polymers, with HOMO values of −5.35 eV for P-IID , −5.48 eV for m F-IID and −5.53 eV for o F-IID , separately. As the result of the HOMO energy levels, polymer solar cells (PSCs) with inverted device configuration by blending the polymers with [6,6]-phenyl-C71 butyric acid methyl ester (PC 71 BM) show continually increased open circuit voltage ( V oc ) from 0.84 V for P-IID to 0.88 V ( m F-IID ) and then a notable value of 0.96 V for o F-IID . However, the fluorination leads to intensively reduced short-circuit current density ( J sc ) of the PSCs, 9.68 mA cm −2 for P-IID , 5.61 mA cm −2 for m F-IID and a very low value of 1.61 mA cm −2 for o F-IID , respectively. Consequently, moderate power conversion efficiency (PCE) of 5.23% is achieved for the non-fluorinated polymer P-IID as well as a decreased value of 2.50% for the meta -fluorinated polymer and a very low PCE of 0.93% for the ortho -fluorinated polymer. These results imply that although fluorine substituted side-chain in the donor unit can effectively deepen the HOMO energy levels of the polymers to obtain enlarged V oc , the absorption losses of the fluorinations caused low J sc should be taken into consideration to design high efficient electron-donating alternating polymers for polymer solar cells. [ABSTRACT FROM AUTHOR]

An alternating fluorinated copolymer based on chlorotrifluoroethylene (CTFE) and butyl vinyl ether (BVE) was synthesized by RAFT/MADIX living/controlled polymerization in the presence of S-benzyl O-ethyl dithiocarbonate (BEDTC). Then, using the obtained poly(CTFE-alt-BVE) as a macro chain transfer agent (macro-CTA), a block copolymer was prepared by chain extension polymerization of vinyl acetate (VAc). After a basic methanolysis process, the poly(vinyl acetate) (PVAc) block was transferred into poly(vinyl alcohol) (PVA). Finally, a novel fluorinated polyurethane with good surface properties due to the mobility of the flexible fluorinated polymer chains linked to the network was obtained via reaction of the copolymer bearing the blocks of PVA with isophorone diisocyanate (IPDI) as a cross-linking agent.

Controlled radical copolymerization of chlorotrifluoroethylene (CTFE) and vinyl acetate (VAc) was successfully achieved in the presence of bis(acetylacetonato)cobalt(II) (Co(acac)2) as a mediated agent and 2,2′-azo-bis-isobutyronitrile (AIBN) as initiator. Both the molar mass and the fluorinated unit content of the copolymer could be controlled, and the chain extension polymerization of the obtained fluorinated copolymer was also achieved.

Bio-based polyamides with high transparency and low yellowness were synthesized using 4,4′-bis(trifluoroacetamido)-α-truxillic acid (ATA-F1) and 4,4′-bis(pentafluoropropionamido)-α-truxillic acid (ATA-F2) as a fluoroalkylated aromatic dicarboxylic acid, and various aromatic diamines. The introduction of fluorine side chains improved the transparency of the polyamide film, and suppressed its yellowness. On the other hand, water repellency, which should be a general characteristic of the fluorinated polymers, was not observed. By using ATA-F1 and various aromatic diamines, aromatic and fluorinated polyamides were obtained. In addition, these also demonstrated a high transparency and a low yellowness index. The heat resistance properties of all the obtained polyamides was over 250 °C, and the characteristics of the bio-based polyamides from 4-aminocinnamic acid derivatives were retained.

Fluorinated polymers generally function as antibacterial agents, but their anti-biofilm effect remains unresolved. This study investigates the efficacy of fluoropolymers containing 2,3,5,6-tetrafluoro- p -phenylenedimethanol (TFPDM) in preventing biofilm formation by Bacillus subtilis and Escherichia coli (Gram-positive and Gram-negative bacterial species). To this end, TFPDM-based acrylate and epoxy polymers (AF and EF, respectively) and their structural analogues without TFPDM (A and E, respectively) were synthesized. All polymers were coated onto polyethylene terephthalate (PET) sheets. Relative to pristine PET, sheets coated with AF reduced the initial bacterial adhesion (72 h) and biofilm formation (30 days) of B. subtilis by 27.6% and 68.7% and of E. coli by 89.2% and 93.8%, respectively. The comparable antibacterial and anti-biofilm efficacies were obtained by sheets with EF. The biofilm detachment was substantially facilitated from the AF, compared with the structural analogue without TFPDM (A). In this comprehensive study, the bacterial adhesion and subsequent biofilm formation were prevented by TFPDM-containing polymers effectively. [ABSTRACT FROM AUTHOR]

Fully self-healing triboelectric nanogenerators (TENGs) capable of recovering damaged triboelectric layers and electrodes are highly desirable as power supplies or self-powered sensors for next-generation electronics. However, the viable application of fully self-healing TENGs is limited due to their poor mechanical and environmental stabilities and output performances. These arise due to the poor mechanical strength, chemical stability, and triboelectric properties exhibited by the triboelectric layers. Herein, a self-healing fluorinated poly(urethane urea) with high mechanical strength, chemical stability, excellent healing efficiency, and outstanding triboelectric performance is synthesized. By sandwiching the self-healing fluorinated poly(urethane urea) with a self-healing ionogel, a fully self-healing TENG named FSI-TENG is obtained with an output power density of 2.75 W m−2, which is the highest compared with other reported fully self-healing TENG. Due to the mechanical strength and chemical stability of the self-healing fluorinated poly(urethane urea), the FSI-TENG exhibits a reliable electrical output performance after being stored at − 30 °C and 90 °C, immersed in corrosive solutions, bent, trampled, and even ran over by a car. Thus, the FSI-TENG can be used for high-output energy generation and as a self-powered sensor to detect water leaks, body movements, and the speed of a car. After damage, the FSI-TENG can be healed to completely restore its electrical output performance, mechanical properties, and environmental stability, ensuring its reliability and service life. [Display omitted] • Self-healing fluorinated poly(urethane urea) (SF-PUU) has been synthesized. • The SF-PUU 1 exhibits triboelectric properties higher than PDMS and PTFE. • A mechanically/environmentally stable SF-PUU-based fully self-healing TENG is obtained. • The fully self-healing TENG has an output power density of 2.75 W m−2. • The fully self-healing TENG can detect water leaks, body movements, and car speed. [ABSTRACT FROM AUTHOR]

Fluorinated amorphous polymeric gate-insulating materials for organic thin-film transistors (OTFTs) not only form hydrophobic surfaces but also significantly reduce traps at the interface between the organic semiconductor and gate insulator. Therefore, these polymeric materials can enhance the OTFT's operation stability. In this study, we synthesized a new polymeric insulating material series composed of acrylate and fluorinated functional groups (with different ratios) named MBHCa-F and used them as gate insulators for OTFTs and in other applications. The insulating features of the MBHCa-F polymers, including surface energy, surface atomic content properties, dielectric constant, and leakage current, were clearly analyzed with respect to the content of the fluorinated functional groups. At higher fluorine-based functional group content, the polymeric series exhibited higher fluorine-based contents at the surface and superior electrical properties, such as field-effect mobility and driving stability, at OTFTs. Therefore, we believe that this study provides a substantial method for synthesizing polymeric insulating materials to enhance the operational stability and electrical performance of OTFTs.