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Brands and products counterfeiting, and falsification are global problems for the development and distribution of high‐tech industrial and food products, which affect world economies. One way to solve these problems is to develop original packaging with protection elements and labeling against counterfeiting, which excludes the possibility of replication and forgery by printing or other methods. The most reliable way to protect packaging from counterfeiting is the use of new materials with unique optical properties and constantly updated technologies for packaging manufacturing and labeling. This paper proposes a new multi‐level technology for the design, manufacture and hidden labeling of polymer packaging made from several layers of transparent polymer films. The design and marking of the multilayer films are combined with perforation, thermal treatment and heat sealing of the package. The reliability of the proposed markings is based on the characterization of optical pleochroism effects in transparent multilayer polymer materials with shape memory. The thermomechanical and optical properties of films made of bulk thermoplastics (polypropylene, polystyrene, polyvinyl chloride and polyethylene) were characterized in polarized light. The modification and combination of these films provide a high color difference and sufficient contrast of hidden markings, allowing to identify genuine products by bar codes formed from shape memory films in sealing seams of flexible polymer packaging. [ABSTRACT FROM AUTHOR]

Bismuthate-borate glasswas synthesized with the compositions (wt.%) 70 Bi2O3, 2 GeO2, 25 B2O3, 3 MoO3; 70 Bi2O3, 17 GeO2, 10 B2O3, 3 MoO3 and 80 Bi2O3, 4 GeO2, 5 MoO3, 11 SiO2; 80 Bi2O3, 8 GeO2, 8.5 SiO2, 3.5 MoO3. Methods were developed for forming a receptor layer on the resulting glass by means of ultrasonic spraying of the interacting components and applying a water-insoluble polymer film obtained via a chemical reaction between the polymer poly-N,N-dimethyl-3,4-dimethylenepyrrolidinium chloride and the modifier potassium hexacyanoferrate (II). The sensors prepared based on these glasses make it possible to determine to within2– 4% the content of hydrogen sulfide and water vapor in air. [ABSTRACT FROM AUTHOR]

Holographic technologies have been envisioned as potentially impacting many areas of everyday life, including science, entertainment, and healthcare, but their adoption is still at an early stage. Recent achievements in flat optics research gave an unprecedented strength to this field, proposing holographic devices as light‐modulating structured surfaces at micro and nanoscale. However, these components are typically static, requiring demanding, burdensome, and irreversible lithographic processes. Here a maskless lithographic framework is reported which only uses light irradiation to fabricate reprogrammable diffractive holographic projectors directly on the surface of a dielectric photomorphable polymer film. Lithographic and characterization optical schemes are combined to optimize in real‐time the light‐modulating performances of the surface, producing holograms with enhanced efficiency. Reprogrammable holograms are then demonstrated to change shape and position according to dynamical optical remorphing of the surface, realizing a proof‐of‐concept of a pixel‐less morphological projector. The approach opens new routes for holographic image displaying and dynamic optical data encoding and sharing. [ABSTRACT FROM AUTHOR]

Composite processing relies heavily on process parameters, which are the key factors that determine the quality of the finished product. In this investigation, carbon fiber (CF)-reinforced polyetherketone (PEK) thermoplastic composites are fabricated through film-fiber stacking and consolidation process. In this method, carbon fabric and polymer film are alternately stacked, and the stacks are then consolidated via compression molding to create a laminate. The mechanical properties of CF/PEK composites are studied in relation to crucial process parameters such as molding temperature, molding pressure, and holding time. To identify the optimal process parameters for CF/PEK fabrication, the tensile and interlaminar shear strengths of these composites were evaluated. Non-linear quadratic equations employing Box-Behnken Design in Response Surface Methodology and validation trials were used to model these features. To obtain the optimal mechanical properties of fabricated composites, the combination of factor ranges was discovered by overlaying contour plots within the practical constraints. The ideal process parameters for achieving maximum mechanical qualities were determined to be around molding temperature of 400°C, a holding period of 60 min, and a molding pressure of 10 bar. [ABSTRACT FROM AUTHOR]

Pharmaceutical films are polymeric formulations used as a delivery platform for administration of small and macromolecular drugs for local or systemic action. They can be produced by using synthetic, semi-synthetic, or natural polymers through solvent casting, electrospinning, hot-melt extrusion, and 3D printing methods, and depending on the components and the manufacturing methods used, the films allow the modulation of drug release. Moreover, they have advantages that have drawn interest in the development and evaluation of film application on the buccal, nasal, vaginal, and ocular mucosa. This review aims to provide an overview of and critically discuss the use of films as transmucosal drug delivery systems. For this, aspects such as the composition of these formulations, the theories of mucoadhesion, and the methods of production were deeply considered, and an analysis of the main transmucosal pathways for which there are examples of developed films was conducted. All of this allowed us to point out the most relevant characteristics and opportunities that deserve to be taken into account in the use of films as transmucosal drug delivery systems. [ABSTRACT FROM AUTHOR]

Nisoldipine (NIS) is a calcium channel blocker that exhibits poor bioavailability (~5%) due to low aqueous solubility and presystemic metabolism in the gut wall. In this context, the present work aimed to develop NIS solid dispersion (NISSD)-based sublingual films using solvent casting technique to improve the dissolution. Phase solubility studies indicated that Soluplus® was the most effective carrier for improving the aqueous solubility of NIS. NISSDs were initially developed using the solvent evaporation method. Fourier transform infrared spectrometric studies were found to display the characteristic vibrational bands related to C=O stretching and N-H deformation in NISSDs, proving the chemical integrity of the drug in NISSDs. Subsequently, bioadhesive sublingual films of NISSDs were formulated using solvent casting method, using hydroxypropyl methyl cellulose (HPMC) E5, E15, and hydroxy ethyl cellulose (HEC EF) as hydrophilic polymers and polyethylene glycol 400 (PEG 400) as plasticizer. The incorporation of NISSDs was found to produce clear films that displayed uniform content. The sublingual film of NISSDs composed of HPMC E5 (2% w/v), was found to display the least thickness (0.29 ± 0.02 mm), the highest folding endurance (168.66 ± 4.50 times), and good bioadhesion strength (12.73 ± 0.503 g/cm2). This film was found to rapidly disintegrate (28.66 ± 3.05 sec) and display near-complete drug release (94.24 ± 1.22) in 30 min. Incorporating NISSDs into rapidly bioadhesive sublingual films considerably improves drug dissolution. Overall, these research outcomes underscored the potential of rapidly dissolving bioadhesive sublingual films to evade gut metabolism and resolve the bioavailability issues associated with oral administration of NIS. [ABSTRACT FROM AUTHOR]

We synthesized a fluorene‐bithiophene co‐polymer with chiral side chains (cPFT2) and investigated its chiroptical properties via synchotronradiation circular dichroism. We observed that thin films of the polymer display an intense circular dichroism (CD) upon annealing, which is of opposite handedness to the CD reported for similar polyfluorenes bearing the same enantiomeric chiral side chain. We then contrast the properties of this polymer with chiral side chain fluorene homopolymer (cPF) and observe large differences in their thin film morphology. Using photoluminescence spectroscopy, we uncover evidence of polymer chain bending in cPFT2, which is further supported by theoretical calculations, and propose an explanation for the observed inverted optical activity. [ABSTRACT FROM AUTHOR]

The values of the surface potentials of two sides of films of polyvinylidene fluoride, and its copolymers with tetrafluoroethylene and hexafluoropropylene, were measured by the Kelvin probe method. The microstructures of the chains in the surfaces on these sides were evaluated by ATR IR spectroscopy. It was found that the observed surface potentials differed in the studied films. Simultaneously, it was observed from the IR spectroscopy data that the microstructures of the chains on both sides of the films also differed. It is concluded that the formation of the surface potential in (self-polarized) ferroelectric polymers is controlled by the microstructure of the surface layer. The reasons for the formation of a different microstructure on both sides of the films are suggested on the basis of the general regularities of structure formation in flexible-chain crystallizing polymers. [ABSTRACT FROM AUTHOR]

The etching of iron alloy items in a H3PO4 solution is used in various human activities (gas and oil production, metalworking, transport, utilities, etc.). The etching of iron alloys is associated with significant material losses due to their corrosion. It has been found that an efficient way to prevent the corrosion of iron alloys in a H3PO4 solution involves the formation of thin complex compound films consisting of the corrosion inhibitor molecules of a triazole derivative (TrzD) on their surface. It has been shown that the protection of iron alloys with a mixture of TrzD + KNCS in a H3PO4 solution is accompanied by the formation of a thin film of coordination polymer compounds thicker than 4 nm consisting of TrzD molecules, Fe2+ cations and NCS−. The layer of the complex compound immediately adjacent to the iron alloy surface is chemisorbed on it. The efficiency of this composition as an inhibitor of iron alloy corrosion and hydrogen bulk sorption by iron alloys is determined by its ability to form a coordination polymer compound layer, as experimentally confirmed by electrochemical, AFM and XPS data. The efficiency values of inhibitor compositions 5 mM TrzD + 0.5 mM KNCS and 5 mM TrzD + 0.5 mM KNCS + 200 mM C6H12N4 at a temperature of 20 ± 1 °C are 97% and 98%, respectively. The kinetic parameters of the limiting processes of hydrogen evolution and permeation into an iron alloy in a H3PO4 solution were determined. A significant decrease in both the reaction rate of hydrogen evolution and the rate of hydrogen permeation into the iron alloy by the TrzD and its mixtures in question was noted. The inhibitor compositions 5 mM TrzD + 0.5 mM KNCS and 5 mM TrzD + 0.5 mM KNCS + 200 mM C6H12N4 decreased the total hydrogen concentration in the iron alloy up to 9.3- and 11-fold, respectively. The preservation of the iron alloy plasticity in the corrosive environment containing the inhibitor under study was determined by a decrease in the hydrogen content in the alloy bulk. [ABSTRACT FROM AUTHOR]

Nanohybrid comprising two-dimensional (2D) materials have surfaced as potential building blocks for manipulating carrier confinement and transportation in electronic devices. The embedded defects in the nanohybrid, more precisely in the semiconductor counterparts, create localized electronic states that primarily impact the carrier transport properties. Herein, nanohybrid of reduced graphene oxide-tin disulfide (rGO-SnS2) with numerous vacancy-induced defect states were synthesized and reinforced with poly (methyl methacrylate) (PMMA), poly (vinylidene fluoride) (PVDF), and PMMA-PVDF (20:80) blend to investigate the memristive characteristics in a metal–insulator–metal (MIM) configuration. XRD analysis demonstrates a comparatively larger crystallite size of SnS2 in rGO-SnS2 nanohybrid (27.31 nm) than in pristine material (15.85 nm), indicating improved nucleation and template-supported growth of SnS2. The nanohybrid encapsulated polymer films promote improved charge transfer through the fillers-encased polymer matrices. The polymer blend featuring rGO-SnS2 displays ferroelectric β-crystal phases with rich sulfur vacancies in the semiconductor counterparts, verified using Electron Paramagnetic Resonance (EPR) analysis. Devices composed of rGO-SnS2 nanohybrid without polymer do not exhibit any memory characteristics. On the contrary, the devices show distinct memory features, such as write-once-read-many (WORM) and bipolar (with ION/IOFF ratio ~ 10–104) behavior, when nanohybrid is reinforced with PMMA and PVDF/or polymer blend. The internal electric field (Ein) in ferroelectric PVDF assists in de-trapping charge carriers from the sulfur vacancies, exhibiting a non-volatile bipolar memory neither observed for PMMA-based devices. Higher surface roughness leads to uneven current distribution and non-uniform switching for nanohybrid-embedded polymer films. A theoretical model is proposed to elucidate the carrier transport mechanism, adhering to Ohm's law, and space charge limited current (SCLC) in the low resistance state (LRS) and high resistance state (HRS), respectively. [ABSTRACT FROM AUTHOR]

In this work, we report on the fabrication, characterization and the third-order nonlinear optical (NLO) properties of basic blue 7 (BB 7) dye‒doped polyvinyl alcohol (PVA) polymer thin films. The absorption spectra of BB 7 dye‒PVA films were measured by UV‒visible absorption studies. The functional groups of BB 7‒PVA films have been identified by FT‒IR spectroscopic analysis. The surface morphology was examined by AFM and SEM analysis which shows that the BB 7 dye‒doped PVA films have a homogenous and smooth surface. The nonlinear absorption and refraction of BB 7‒PVA films were respectively explored by open aperture and closed aperture Z‒scan technique using a 5 mW semiconductor diode laser of 635 nm wavelengths. The BB 7‒PVA films exhibit the reverse saturable absorption (RSA) and self-defocusing effect and the measured third‒order nonlinear susceptibility χ(3) values of these films were found to be of the order of 10− 5 esu. The present experimental results show that BB 7‒PVA films may have potential applications in future photonic and NLO devices. [ABSTRACT FROM AUTHOR]

PL enhancement of QD-polymer films with CO 2 micropores and microparticles. [Display omitted] Quantum-dot (QDs) polymer composite films, which are key components in recent display applications, require improved photoluminescence (PL) intensity and color conversion efficiency for better display quality and low power consumption. In this study, we developed a novel approach to improve the photoluminescence (PL) of quantum dot (QDs)–polymer nanocomposite films. This was achieved by incorporating CO 2 micropores and scattering particles into QD-embedded photopolymerizable polymer films. CO 2 micropores were generated by the decomposition of KHCO 3 in the film. The CO 2 micropores, along with the partially decomposed KHCO 3 microparticles, act as a scattering medium that increases the photon absorbance and improves the PL intensity. The effect of KHCO 3 annealing temperature on various optical properties is investigated, and it is found that a large number of uniform micropores are created in the film at an optimal temperature, 110 ℃. Compared to an ordinary QD-polymer film, the PL of the QD-hybrid-foamed polymer film increases by 4.2 times. This method is fast and economically efficient, and provides insights into the design of high-performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

The casting technique was used to fabricate carboxymethylcellulose (CMC), polyvinyl alcohol (PVA), and PVA/CMC blend films. The sensitivity of the prepared films to irradiation was examined by applying gamma radiation with an intensity of 100 kGy. Structural and optical properties of unirradiated and gamma-irradiated films were investigated using Fourier-transform infrared (FTIR) and UV–Vis spectroscopy, respectively. Photoluminescence spectra were recorded for polymer films before and after exposure to gamma rays. The PVA film has a higher transmittance than the CMC film and PVA/CMC blend films. Moreover, the film's transmittance decreases when exposed to 100 kGy gamma rays, especially in the UV region. The optical bandgap (Eg) values are 5.75 eV and 5.60 eV for pure PVA and pure CMC, respectively. While for blended films it is lessened to about 5.50 eV for PVA–12%CMC blend film. Moreover, these values are slightly decreased after irradiation with gamma-ray to about 5.70, 5.55, and 5.45 eV for pure PVA, pure CMC, and PVA–12%CMC blend films. While the refractive indices values are 1.965, 2.024, and 2.355 for pure PVA, pure CMC, and PVA–12%CMC blend, respectively. These values decreased after exposure to gamma-ray to about 1.959, 2.016, and 2.256 for pure PVA, pure CMC, and PVA–12%CMC blend, respectively. [ABSTRACT FROM AUTHOR]

In this research, polyvinyl alcohol (PVA)-chitosan composite films were produced using nanocellulose from coconut fibers (Cocos nucifera) in an Indonesian plantation in order to enhance mechanical properties and biodegradability. The process began by separating lignin and hemicellulose by delignification, bleaching, and then cellulose hydrolysis to produce nanocellulose. The PVA was mixed with chitosan with specific compositions and added the nanocellulose in 0%, 1%, 3%, and 5% concentrations, respectively. A tensile test was conducted to obtain tensile strength and elongation break. Biodegradability test was also carried out to determine the level of mass losses. Based on SEM observations, addition of nanocellulose appears to increase the reactivity of the formation of PVAchitosan composite films, which are characterized by a reduction in film thickness. Addition of 5% nanocellulose resulted in a high quality of nano-composite. The tensile strength, fracture elongation and biodegradability of the composite film were 31.50 MPa, 39.9% and 9.04%, respectively. [ABSTRACT FROM AUTHOR]

Wrinkled ferroelectric polymer films with out‐of‐plane deformation exhibit exotic strain fields that differ from those of conventional epitaxial film systems, offering a new path toward manipulating electrical and mechanical behaviors in ferroelectrics. However, the direct observation of the domain structure evolution in ferroelectric polymer films during continuous deformation is challenging with current experimental approaches. In this study, the strain‐induced evolution of toroidal domain structures in organic poly(vinylidene fluoride‐ran‐trifluoroethylene) (P(VDF‐TrFE)) films with concentric toroidal wrinkle patterns is comprehensively investigated using phase‐field simulations. The results reveal morphology‐ and thickness‐dependent toroidal polar topology in wrinkled P(VDF‐TrFE) films. External strain loading can modulate this ferroelectric domain, which exhibits robust coupling behavior with a mixed strain field of periodic tensile and compressive strains. It is demonstrated that toroidal wrinkled ferroelectric films provide an effective and unique flexible platform for continuously controllable strain engineering in ferroelectrics and a theoretical framework with potential applications in flexible electronic devices. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of the properties of a new composite material made from poly(vinyl chloride) plastisol (PVC) and conifer-derived wood flour. The material can be used for thermal insulation, floor coverings with high resistance to mechanical trauma, and protective coatings. The plastisol was made from emulsion poly(vinyl chloride), the plasticiser was bis(2-ethylhexyl) adipate, and the stabiliser was octyltin mercapeptide. Two types of flour were used: fine-grained and coarse-grained. Its properties, such as bulk density, oil number, and plasticiser number, were determined. The polymer-wood composite contained 20 or 30 wt.% wood flour in PVC. Plastisol was obtained by repeated mixing, mashing, and venting under vacuum. The produced composite material was gelated at temperatures of 130, 150, and 170 °C. The gelation process of the composites was studied in a Brabender apparatus. Samples in the form of polymer films were used to study density, hardness, thermal stability, and mechanical and thermomechanical properties. The structure of the composites was observed by scanning electron microscopy (SEM). A summary of all test results showed that composite films made from PVC plastisol with 20 wt.% of fine wood flour gelled at 150 °C had the most favourable physical, mechanical, and thermal properties. [ABSTRACT FROM AUTHOR]

Micropores fabricated on organic polymer films have a wide range of applications in fields such as microfiltration, new energy, and biomedical separation. The use of laser processing technology can complete the processing of micropores on the surface of ultrathin films with high precision, but there is still some difficulty in the processing of ultrathick films. In this paper, a picosecond ultraviolet (UV) laser was used to explore the high-precision manufacturing process of micropores on the surface of ultrathick polyimide (PI) films. The effects of laser power, laser frequency, and scanning speed on the cone angle and spatter deposition area of micropores' fabrication on ultrathick PI were studied based on orthogonal experiments. The mechanism of processing micropores on ultrathick PI was analyzed by studying the deposition area and morphology of the spatter generated during the laser ablation process. It was found that high-quality micropores can be fabricated at low laser frequency and high power. [ABSTRACT FROM AUTHOR]

Microfluidic devices with a free-standing structure were printed directly on polymer films using the functional materials that form interconnected pores. The printed devices can transport fluids by capillary action in the same fashion as paper-based microfluidic devices, and they can handle much smaller sample volumes than typical paper-based devices. Detection of glucose was performed using both colorimetric and electrochemical methods, and the observed limits of detection (LOD) were similar to those obtained with paper-based microfluidic devices under comparable testing conditions. It is demonstrated that printed microfluidic devices can be fabricated using printing processes that are suitable for high-volume and low-cost production and that the integration of microfluidic channels with electrodes is straightforward with printing. Several materials that are printable and form interconnected pores are presented. [ABSTRACT FROM AUTHOR]

Recently, organic electrochemical transistor (OECT) has been extensively studied as an emerging flexible electronic due to its high transconductance, biocompatibility, and capability of ion-to-electron transformation. To further promote the application of OECTs in bioelectronics, n-type and p-type conducting polymers with comparable performance are required. However, recent studies typically focus on the p-type OECTs, while the development of n-type OECT suffers from the instability and low electrical performance of the electron-transporting polymers. Here, a strategy to improve the n-type OECT transconductance that the construction of the carbon nanotube network in the channel to enhance the carrier transport efficiency was reported. The transconductance of poly(benzimidazobenzophenanthroline) (BBL)/single-walled carbon nanotubes hybrid film OECT was improved by ~15 times of the pristine BBL OECTs, and the operational stability in the aqueous environment was also enhanced. Furthermore, the carbon nanotube network mitigates the transconductance degradation of the flexible devices induced by crack damage, and the mechanism of the performance enhancement was clarified. [ABSTRACT FROM AUTHOR]

Liquid crystalline polymer networks (LCN) with azobenzene monomers bend reversibly under UV‐light irradiation, combining photomechanical and photothermal effects. However, the harmful nature of UV‐light limits their use in biology and soft robotics. Although visible light‐absorbing tetra‐ortho‐fluoro‐substituted azobenzenes exist, liquid crystalline monomers have never been prepared. Previously, such azobenzenes were added as photoactive additives (up to 10%) to otherwise passive liquid crystalline polymer networks. In this work, a molecular design of a liquid crystalline, polymerizable azobenzene switchable by visible light is presented. The monomer assembles in a highly fluid nematic phase, but polymerizes in a layered smectic C phase. The films are produced solely from the monomer without additional liquid crystalline components and are actuated with visible light. Bending experiments in air and under water differentiate photomechanical and photothermal effects. Remarkably, a 60 µm splay aligned film maintains its deformation for hours, slowly reverting over days. Monomer liquid crystallinity is characterized using differential scanning calorimetry (DSC), wide‐angle X‐ray scattering (WAXS), and polarized optical microscopy (POM); polymer films are analyzed using WAXS and DSC on a homogeneously aligned film. The synthetic procedure is high yielding and polymer film fabrication is scalable, which enables the use of safe and efficient photomechanical LCNs in soft robotics, engineering and biology. [ABSTRACT FROM AUTHOR]

The focus of the present work is to prepare low‐density polyethylene (LDPE)‐graphene (G) nanocomposite films with improved gas barrier properties by melt extrusion. A narrow range of the graphene (0.05–0.3 wt.%) as filler was used in the LDPE matrix. The rheological analysis indicating that there is no significant influence on the LDPE chains mobility with the addition of filler. The nanocomposites percent crystallinity (Xc%) increase from 25.0% to 31.6% compared to neat LDPE. The X‐ray diffractogram shows a change in width half height of the peak positioned at 26° ((002) plane) from 0.69 (graphite) to 1.24 (graphene), revealing the asymmetry of this plane. The optical microscopy images show a good dispersion of the nanoparticles in the polymer matrix. The mechanical properties of the nanocomposites in longitudinal direction demonstrate better improvement with addition of the filler as compared to the transverse direction. The contact angle measurements of nanocomposites for water and ethylene glycol do not shows a significant variation in comparison to neat LDPE. The nanocomposites show 26% enhancement in the oxygen barrier property. Thus, here we present the cost‐effective LDPE‐graphene nanocomposites with improve oxygen barrier property, which can be used in different industrial application especially in food packaging. [ABSTRACT FROM AUTHOR]

Understanding how small molecules penetrate and contaminate polymer films is of vital importance for developing protective coatings for a wide range of applications. To this end, rhodamine B fluorescent dye is visualized diffusing through polystyrene‐polydimethylsiloxane block copolymer (BCP) coatings using confocal microscopy. The intensity of dye inside the coatings grows and decays non‐monotonically, which is likely due to a combination of dye molecule transport occurring concurrently in different directions. An empirical fitting equation allows for comparing the contamination rates between copolymers, demonstrating that dye penetration is related to the chemical makeup and configuration of the BCPs. This work shows that confocal microscopy can be a useful tool to visualize the transport of a fluorophore in space and time through a coating. [ABSTRACT FROM AUTHOR]

The intelligent response actuators based on bilayer polymer can deform under the stimulation of temperature, humidity, light, and other external environment, which is the focus of research. However, achieving multiple responses, high deformation, and programmability is still one of the challenges for these actuators. Herein, a nondetachable bilayer structure, polylactic acid–polypropylene carbonate/polyvinyl alcohol–polydopamine (PLA–PPC/PVA–PDA) multiresponse programmable actuator is prepared by a simple scraping film method. Using PLA–PPC as the solvent‐driven response layer, the effects of length, thickness, shape, and solvent vapor on the deformation of PLA–PPC/PVA–PDA actuators are studied. Among them, the high curvature of the film stimulated by ethyl acetate (EA) solution is 29.85 cm−1. Using PVA–PDA as the response layer to water molecules and infrared (IR) light, the bilayer film shows excellent curling performance. Moreover, the dynamic processes of human clothing and biomimetic squid under solvent stimulation, the picture rolling motion under water molecule stimulation, the biomimetic flower blooming and merging under the synergistic of water molecules and IR light, and the deformation process of biomimetic mimosa under the competition between water molecules and IR light are simulated, which broadens the road for the development of intelligent driving materials. [ABSTRACT FROM AUTHOR]

Currently, there is considerable interest in seeking an environmentally friendly technique that is neither thermally nor organic solvent-dependent for producing advanced polymer films for food-packaging applications. Among different approaches, plasma polymerization is a promising method that can deposit biodegradable coatings on top of polymer films. In this study, an atmospheric-pressure aerosol-assisted plasma deposition method was employed to develop a poly(ethylene glycol) (PEG)-like coating, which can act as a potential matrix for antimicrobial agents, by envisioning controlled-release food-packaging applications. Different plasma operating parameters, including the input power, monomer flow rate, and gap between the edge of the plasma head and substrate, were optimized to produce a PEG-like coating with a desirable water stability level and that can be biodegradable. The findings revealed that increased distance between the plasma head and substrate intensified gas-phase nucleation and diluted the active plasma species, which in turn led to the formation of a non-conformal rough coating. Conversely, at short plasma–substrate distances, smooth conformal coatings were obtained. Furthermore, at low input powers (<250 W), the chemical structure of the precursor was mostly preserved with a high retention of C-O functional groups due to limited monomer fragmentation. At the same time, these coatings exhibit low stability in water, which could be attributed to their low cross-linking degree. Increasing the power to 350 W resulted in the loss of the PEG-like chemical structure, which is due to the enhanced monomer fragmentation at high power. Nevertheless, owing to the enhanced cross-linking degree, these coatings were more stable in water. Finally, it could be concluded that a moderate input power (250–300 W) should be applied to obtain an acceptable tradeoff between the coating stability and PEG resemblance. [ABSTRACT FROM AUTHOR]

The polyethylene lithium-ion battery separator is coated with a polymer by means of a roll-to-roll (R2R) gravure coating scheme to enhance the thermal stability. The polyvinylidene fluoride (PVDF) or polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) is gravure-coated, and the pores are fabricated based on online nonsolvent-induced phase separation (NIPS). N-methylpyrrolidone is used as a solvent, and deionized water or a methanol mixture thereof is exploited as a nonsolvent in NIPS. Scanning electron microscopy confirms that the polymer film is formed and that the pores are well developed. The thermal shrinkage decreased by 20.0% and 23.2% compared to that of the bare separator due to the coating of PVDF and PVDF-HFP, respectively. The R2R gravure coating scheme is proven to be fully functional to tailor the properties of lithium-ion battery separators. [ABSTRACT FROM AUTHOR]

With the progressive development of photomultiplication‐type organic photodetectors (PM‐OPDs), increasing research efforts are devoted to all‐polymer PM‐OPDs due to their potential in terms of device stability and stretchability. However, poor polymer‐polymer miscibility and entanglement of long polymer chains are still the main challenges to form desirable active layer morphology in such systems. A smooth solidification process is favorable toward realizing a morphology that features ordered molecular orientation and high crystallinity. Herein, morphological control issue in all‐polymer PM‐OPDs is addressed by modifying film formation kinetics with an insulating polymer blending strategy. The prolonged crystallization process of polystyrene‐blended films can form high‐ordered molecular arrangements and crystallinity in donor/acceptor phases, leading to improved charge transport properties and suppressed trap states. With boosting the trap‐assisted photomultiplication effect, the polystyrene‐blended all‐polymer PM‐OPD with a high specific detectivity of 4.0 × 1013 Jones can be achieved due to the accumulation of enhanced photogenerated electrons at the interface and the efficient injection of external holes, which is one of the best detectivity values reported for PM‐OPDs. This study not only reveals valuable insights into the effects of insulating polymers on the film formation kinetics mechanism, but also provides novel strategy to fabricate high‐performance all‐polymer PM‐OPDs. [ABSTRACT FROM AUTHOR]

Artificial actuators have been extensively studied due to their wide range of applications from soft robotics to biomedicine. Herein we introduce an autonomous bi-enzymatic system where reversible motion is triggered by the spontaneous oxidation and reduction of glucose and oxygen, respectively. This chemo-mechanical actuation is completely autonomous and does not require any external trigger to induce self-sustained motion. The device takes advantage of the asymmetric uptake and release of ions on the anisotropic surface of a conducting polymer strip, occurring during the operation of the enzymes glucose oxidase and bilirubin oxidase immobilized on its surface. Both enzymes are connected via a redox polymer at each extremity of the strip, but at the opposite faces of the polymer film. The time-asymmetric consumption of both fuels by the enzymatic reactions produces a double break of symmetry of the film, leading to autonomous actuation. An additional break of symmetry, introduced by the irreversible overoxidation of one extremity of the polymer film, leads to a crawling-type motion of the free-standing polymer film. These reactions occur in a virtually unlimited continuous loop, causing long-term autonomous actuation of the device. Owing to their interesting applications from soft robotics to biomedicine, methodologies to produce artificial actuators are desirable. Herein the authors develop an autonomous soft bioelectrochemical actuator with self-sustained motion triggered by spontaneous enzymatic reactions. [ABSTRACT FROM AUTHOR]

Muscle groups perform their functions in the human body via bilateral muscle actuation, which brings bionic inspiration to artificial robot design. Building soft robotic systems with artificial muscles and multiple control dimensions could be an effective means to develop highly controllable soft robots. Here, we report a bilateral actuator with a bilateral deformation function similar to that of a muscle group that can be used for soft robots. To construct this bilateral actuator, a low-cost VHB 4910 dielectric elastomer was selected as the artificial muscle, and polymer films manufactured with specific shapes served as the actuator frame. By end-to-end connecting these bilateral actuators, a gear-shaped 3D soft robot with diverse motion capabilities could be developed, benefiting from adjustable actuation combinations. Lying on the ground with all feet on the ground, a crawling soft robot with dexterous movement along multiple directions was realized. Moreover, the directional steering was instantaneous and efficient. With two feet standing on the ground, it also acted as a rolling soft robot that can achieve bidirectional rolling motion and climbing motion on a 2° slope. Finally, inspired by the orbicularis oris muscle in the mouth, a mouthlike soft robot that could bite and grab objects 5.3 times of its body weight was demonstrated. The bidirectional function of a single actuator and the various combination modes among multiple actuators together allow the soft robots to exhibit diverse functionalities and flexibility, which provides a very valuable reference for the design of highly controllable soft robots. [ABSTRACT FROM AUTHOR]

The consequences of light‐induced oxidation of polycarbonate on its permeability to oxygen were deeply investigated. Polymer films were sequentially photoaged, resulting in the sequential appearance and growth of oxidation products at the surface of the exposed side up to a limit value, owing to the progressive yellowing of the film during the photoageing process. Such effect restricts drastically the oxidation process to the film surfaces. The observed decrease in oxygen permeability consecutive to exposure of only one side of the film results principally from a decrease in oxygen solubility into the polymer, with a minor reduction of its diffusion ability. This was explained by the increase of the polymer polarity owing to the appearance of several types of polar chemical groups (namely CO and OH) as well as the occurrence of cross‐linking upon photodegradation. This decrease in oxygen permeability is then a positive feature in the case of applications for packaging and medical components. No further decrease in oxygen permeability was observed when the second side of the films was photooxidized, which can be explained by a "funnel effect" type between sorption, diffusion and desorption steps. [ABSTRACT FROM AUTHOR]

Biodegradable polymer films composed of Iota-Carrageenan and Copper Sulphate Pentahydrate (CuSO4.5H2O) were prepared by using the Solution Casting process. To investigate the optical property, different wt.% of CuSO4.5H2O were added to I-carrageenan polymer films. X-Ray diffraction analysis was used to study the structural properties of prepared electrolytes. FTIR study revealed the complexation between the polymer and the salt. The increase in the amorphous nature of the film by the addition of the salt was confirmed using an X-Ray Diffraction (XRD) pattern. The functional group and interaction between the different components present in the polymer film are observed from Fourier Transform Infrared (FTIR) analysis, implying that the addition of (CuSO4.5H2O) salt causes microstructural differences in the polymer film. The UV-Visible Spectrometer was used to record the optical properties like the absorption coefficient, extinction coefficient, and optical bandgap energy of the polymer blend electrolytes. From this, it was observed that the absorption value was increased with the addition of salt. The optical band gap was also recorded and it was observed that 20 wt.% of CuSO4.5H2O added film was found to have a higher energy gap (4.3 eV) compared with the other. [ABSTRACT FROM AUTHOR]

Dynamic scattering has been a prominent technique in the display industry for several years. However, conventional approaches have required the use of tailored conductive layers to enable modular control in display panels. This has resulted in an increase in process complexity and device cost. To overcome these limitations, the present work proposes a novel method for fabricating a patterned dynamic scattering film using masked photopolymerization of liquid crystalline epoxy in negative liquid crystals. Specifically, the film is sandwiched between two fully covered electrodes, and an electric field is applied causing dynamic scattering only in the area that had been exposed to ultraviolet light during the preparation process. The remaining area remained transparent. The underlying mechanism is attributed to the formation of polymer solely in the UV‐exposed region via masked photopolymerization. This polymer is capable of absorbing ions, resulting in the formation of a concentration gradient of ions between the UV‐exposed and unexposed areas. The low concentration of ions in the unexposed area prevents the induction of dynamic scattering under an electric field, leading to the patterned dynamic scattering phenomenon. Building on this mechanism, the researchers are able to achieve several multilevel patterned dynamic scattering films sandwiched between two fully covered electrodes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A core feature of two‐dimensional covalent organic frameworks is crystallinity, but it remains challenging to gain their thin films with high crystallinity. Here, we presented growth of thin films of two‐dimensional covalent organic frameworks with an average domain size of ~2.83 μm2 and maximum domain size of up to ~26.19 μm2 using amphiphilic glycine derivatives on water surface. We envisage that this work will inspire the growth of a wide variety of organic two‐dimensional materials with high crystallinity and boost their structure property investigations. [ABSTRACT FROM AUTHOR]

Hybrid bond layers (BLs) were designed, fabricated, and evaluated for cold spray metallization of CFRP. The bond layers consisted of metal mesh embedded in a polymer film adhesive co-cured to the CFRP. Efforts were devoted to identifying the critical opening ratio—i.e., the ratio of mesh opening size to powder diameter, for deposition of an adherent coating. Analysis of powder deposited at mesh openings show a transition from erosion (at a mesh opening ratio of 6.4) to mechanical interlocking and formation of a continuous coating with decreasing opening ratio. Selection of opening ratio yielded either (a) a grid of consolidated thin-walled deposits atop mesh wires separated by microchannel openings, or (b) densified coatings of cold-sprayed Ti. The effective opening ratio increased with increasing diameter ratio—i.e., the ratio of wire diameter to powder size, a consequence of eroded wire peripheries at shallow impact angles. These findings inform the design of future hybrid BLs, in concert with the selection of powder size, for cold spray metallization of CFRP. [ABSTRACT FROM AUTHOR]

Rubbing‐induced alignment of conjugated polymers is systematically investigated in terms of intra‐ and inter‐molecular interaction. Various polymer films with a broad range of polymer chain rigidity are rubbed, and the degree of polymer chain alignment is quantitatively characterized. The rubbing technique effectively aligns crystalline domains in conjugated polymer films when the temperature approaches the critical rubbing temperature (Trc$T_{\mathrm{r}}^{\mathrm{c}}$), at which the rearrangement and the slip of polymer chains are possible. A polymer with significant intra‐/inter‐molecular interactions exhibits higher Trc$T_{\mathrm{r}}^{\mathrm{c}}$, though quantitative analysis reveals an intermediately aligned state at temperature Tr′ lower than Trc$T_{\mathrm{r}}^{\mathrm{c}}$. This state originates from polymer chain aggregation in an amorphous domain. The intermediately aligned state can be controlled by plasticizer, which enables low‐temperature alignment of high‐mobility polymer film by reducing Tr′ to near 100 °C, increases the crystallinity, and improves the alignment effect at this state comparable to that of the completely aligned state obtained at extremely high temperatures. [ABSTRACT FROM AUTHOR]

Increasing consumer awareness of the impact of nutrition on health and the growing popularity of vegan diets are causing a need to look for new plant-based formulations of standard confectionery products with high energy density and low nutritional value, containing gelatin. Therefore, the aim of this study was to develop vegan and sugar-free gummy jellies based on an algae-derived polysaccharide—furcellaran (FUR). Until now, FUR has not been used as a gel-forming agent despite the fact that its structure-forming properties show high potential in the production of vegan confectionery. The basic formulation of gummy jellies included the addition of soy protein isolate and/or inulin. The final product was characterized regarding its rheological, antioxidant, mechanical and physicochemical properties. Eco-friendly packaging for the jellies composed of a three-layer polymer film has also been developed. It was observed that the highest values of textural parameters were obtained in jellies containing the addition of soy protein isolate, whose positive effect was also found on antioxidant activity. Before drying, all furcellaran-based gel systems showed G' and G" values characteristic of strong elastic hydrogels. Storing jellies for a week under refrigeration resulted in an increase in hardness, a decrease in moisture content and reduced water activity values. Overall, our study indicates the high potential of furcellaran both as a gelling agent in confectionery products and as a base polymer for their packaging. [ABSTRACT FROM AUTHOR]

Radiative cooling is a new large-scale cooling technology with the promise of lowering costs and decreasing global warning. Currently, daytime radiative cooling is achieved via the application of reflective metal layers and complicated multilayer structures, limiting its application on a massive scale. In our research, we explored and tested the daytime subambient cooling effect with the help of single-layer films consisting of BaSO4, TiO2, and BaSO4/TiO2 microparticles embedded in PVDF/PTFE polymers. The film, consisting of BaSO4/TiO2 microparticles, offers a low solar absorbance and high atmospheric window emissivity. The solar reflectance is enhanced by micropores in the PVDF/PTFE polymers, without any significant influence on the thermal emissivity. The BaSO4/TiO2/PVDF/PTFE microparticle film attains 0.97 solar reflectance and 0.95 high sky-window emissivity when the broadly distributed pore size reaches 180 nm. Our field test demonstrated that the single-layer BaSO4/TiO2/PVDF/PTFE microparticle film achieved a temperature 5.2 °C below the ambient temperature and accomplished a cooling power of 74 W/m2. Also, the results show that, when the humidity rises from 33% to 38% at 12:30 pm, it hinders the cooling of the body surface and lowers the cooling effect to 8%. [ABSTRACT FROM AUTHOR]

A comparative study of anticorrosive inhibited polymer films on the tungsten surface formed from an aqueous solution of inhibited formulations (INFOR) containing organosilane and corrosion inhibitors was carried out by means of the prolonged exposure of a tungsten product in a modifying solution and by the method of cataphoretic deposition (CPD). Depending on the method of forming films on tungsten, the molecular organization of the near-surface layers was studied (ATR-FTIR), and the subprimary structure of the films was explored (TEM). The optimal modes of cataphoresis deposition (CPD duration and current density applied to the sample) for the formation of a protective inhibited polymer film on the tungsten surface were established by means of SEM. The energy and thermochemical characteristics (sessile drop and DSC methods), as well as operational (adhesive behavior) and protective filming ability (EIS and corrosion behavior), according to the method of formation of inhibited polymer film, were determined. Based on the combined characteristics of the films obtained by the two methods and the deposition modes, the CPD method showed better performance than the electroless dipping method. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) undergoes degradation through the action of microorganisms and enzymes that can degrade it by composting. The goal of this work was to observe the degradation/disintegration behavior in garden soil of neat PLA and PLA composites with 3 wt% cellulose nanocrystals (CNC) modified or not with non-ionic surfactants (S) at a weight ratio of 1:1 (CNC:S). Four types of non-ionic surfactants with hydrophilic-lipophilic balance (HLB) ranging from 4.3 to 16.7 were tested: sorbitan monolaurate (Span 20), sorbitan monooleate (Span 80), polyoxyethylene sorbitan monolaurate (Tween 20) and polyoxyethylene sorbitan monooleate (Tween 80). Films were obtained by solution casting, cut into 2 × 2 cm strips and buried in garden soil, while monitoring the temperature and humidity for 150 days. Changes in the films by visual inspection, polarized light microscopy, thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR) were observed. Results showed that the addition of surfactants favored the rate of biodegradation of the composites, being the lowest molecular weight the determinant property of the surfactant to enhance biodegradation rate of PLA/CNC/S composites. Nevertheless, for surfactants belonging to the same chemical family, the highest biodegradation rate for PLA/CNC/S composite obeys the principle of high HLB, and low spherulite size. [ABSTRACT FROM AUTHOR]

This work shows the development and optimization of simultaneous 193 nm LA-ICP-MS & LIBS methods for the spatially resolved analysis of polymer thin films of polyimide, polystyrene, and polyvinylpyrrolidone, which were exposed to a UV treatment and weathered in a corrosive atmosphere containing hydrogen sulfide, to investigate polymer ageing and degradation in harsh environments. Evaluating the information from a broadband multichannel LIBS instrument enabled the spatially resolved discrimination of the used polymer types with a lateral resolution of 40 μm. At the same time, a high-resolution spectrometer with an ICCD camera could detect oxidation derived from the UV treatment, and ICP-MS data could measure differences in the sulfur uptake derived from the sample film H2S weathering. In additional experiments, the depth resolution was optimized, depending on the polymer type to 150–360 nm, to gain information on the H2S diffusion profile and the sample depth affected by oxidation. Matrix-matched standards were used to calibrate the ICP-MS, enabling simultaneous determination of quantitative sulfur diffusion profiles and the influence of the UV treatment on the diffusion profiles. The capabilities of the combined measurement methods based on a 193 nm laser are well demonstrated on the differently treated polymer thin film samples used in this work, revealing spatially resolved information on different oxidation behavior, different sulfur diffusion profiles, and a significant decrease of the sulfur uptake in UV treated films – information that is not accessible with setups in previous literature. [ABSTRACT FROM AUTHOR]

[Display omitted] Integration of ultralow surface energy and surface functionality on one surface coatings is highly desirable in chemical and biomedical applications. However, it is a fundamental challenge to reduce surface energy without cost of surface functionality and vice versa. To address this challenge, the present work made use of the rapid and reversible change of surface orientation conformations of weak polyelectrolyte multilayers to create ionic, perfluorinated surfaces. Poly(allylamine hydrochloride) (PAH) chains and the micelles of sodium perfluorooctanoate (SPFO) were layer-by-layer (LbL) assembled into (SPFO/PAH) n multilayer films, which readily exfoliated to freestanding membranes. The static and dynamic surface wetting behaviors of the resulting membranes were studied by sessile drop technique and their surface charge behaviors in water by electrokinetic analysis. As-prepared (SPFO/PAH) n membranes exhibited ultralow surface energy in air; the lowest surface energy is 2.6 ± 0.5 mJ/m2 for PAH-capped surfaces and 7.0 ± 0.9 mJ/m2 for SPFO-capped surfaces. They readily became positively charged in water, which allowed not only effective adsorption of ionic species for further functionalization with subtle change in surface energy, but effective adhesion onto various solid substrates such as glass, stainless steel, and polytetrafluoroethylene to endorse the wide applicability of (SPFO/PAH) n membranes. [ABSTRACT FROM AUTHOR]

Copolymer thin films with two types of functional groups have excellent performance as sensors, for example. The formation and deposition of allyl alcohol‐acrylic acid copolymer films by pulsed high frequency plasma is a complex process. As usual, the chemical composition of the top surface of the films was investigated by XPS and FTIR measurements. Furthermore, contact angle measurements with water were used to characterise the hydrophilicity and wettability of the polymer films. After plasma deposition, a significant decrease in functional groups (OH and COOH) was observed compared to the classically copolymerised equivalent. The remaining functional groups, i.e. the majority of these groups, were sufficient for application as sensor layers. Segmental mobility and conductivity, important for sensor applications, were analysed by broadband dielectric spectroscopy. [ABSTRACT FROM AUTHOR]

Experimental data presented in the literature on the depth of processing of polymer films using low-temperature plasma are considered. Changes in the chemical composition and structure along the depth of the samples have been studied using the modern experimental techniques of X-ray photoelectron spectroscopy, secondary ion mass spectrometry, and transmission electron microscopy; precision etching was carried out with an Ar+2500 cluster beam; and the pit depth was measured by profilometry. It has been found that the thickness of the modified layer is ≤50 nm and depends relatively little on the polymer nature. [ABSTRACT FROM AUTHOR]

We prepared a blue phase (BP) liquid crystal mixture consisting of a T-shaped nematic liquid crystal, a chiral dopant, a reacting monomer mixture and a photo-initiator. It exhibited a phase sequence of Iso-BPIII-cubic BP-N* on cooling. We produced the polymer stabilised cubic BP (PS-cubic BP) and BPIII (PS-BPIII). After washing low-molar-mass materials from each PS-BP, we obtained the corresponding polymer networks. Marked difference exhibited in a three-dimensional structure between the BPIII and cubic BP polymer networks. Although they were prepared by the photopolymerisation of achiral monomers, they showed optical activities. Furthermore, they proceed the helical polymerisation of achiral reactive monomers to produce a chiral polymer film. The optical handedness of the polymer film is corresponded to that of the original BP. We discuss how the chirality is transferred from each BP to the corresponding polymer film. [ABSTRACT FROM AUTHOR]

Polymer-dispersed liquid crystal (PDLC) films are widely used in intelligent opto-electronic field owing to their electrically switchable properties. Previous studies have focused on the improvement of electro-optical properties of PDLC film in visible light bands; yet, the application of PDLC in other bands has few research. In this paper, vinylferrocene was introduced into PDLC films containing polyhedral oligomeric silsesquioxane (POSS) to improve UV-shielding properties. Scanning electron microscopy (SEM) studies revealed that vinylferrocene was uniformly dispersed in the polymer network. The structure could improve the electro-optical properties of PDLC film. The effect of temperature on PDLC film was studied. When the temperature reached 35°C, the PDLC composite film polymer network had better electro-optical properties. The PDLC composite films can effectively shield 86.73% UV light at on-state and 93.37% at off-state. The unique UV-shielding properties make this PDLC film a great application potential in smart windows. This PDLC combined with POSS and vinylferrocene film also exhibits large-area processability, which can further expand its application. [ABSTRACT FROM AUTHOR]

Measuring Young's modulus (YM) at a small indentation depth for polymer thin films has been critical in predicting their adhesion properties using atomic force microscopy (AFM). This paper provides adhesion force maps of copolymer thin films composed of methacrylate-based monomers with different bulky substituents added to 2-hydroxyethyl methacrylate (HEMA) using AFM. Then Derjaguin–Müller–Toporov (DMT) fitting model was used to generate YM maps of these copolymers and their homopolymers. For example, using the DMT model, the YM value of 15% phenoxyethyl methacrylate (PhEMA, -OPh): 85% HEMA copolymer is greater than HEMA homopolymer, suggesting that the combination resulted in a stiffer polymer material. The observations indicated that methacrylate-based copolymers with bulky substituents such as -OPh may exhibit higher YM resulting in stiffer polymer thin films. [ABSTRACT FROM AUTHOR]

Colorectal cancer, which is difficult to treat and has a high recurrence rate, is a challenging target. Here, we propose a novel multi-layered sheet-like device with photothermal switching for the achievement of both hyperthermia and local chemotherapy. The device was fabricated by modifying polydopamine on the surface of a polymer thin film (nanosheet) and combining it with a drug-loaded poly(lactic acid) nanosheet, and was demonstrated to control the drug release reversibly. It is suggested that several percent of loaded drug was repeatedly released by irradiating near-infrared light, indicating the high potential of minimally invasive long-term treatment of colorectal cancer. [ABSTRACT FROM AUTHOR]

Force sensing resistor (FSR) is a passive component that is composed of polymer thick films that change resistance between its terminals due to force applied at its surface. FSRs inherently exhibit many nonlinear behaviors. This work employs a Genetic Algorithm agent to navigate the search space to identify the optimal modeling systems for five circular FSRs of comparable sizes. The Hybrid GA-System Identification allows the globally optimized models for the original systems to be identified without the need of a differentiable measure function or linearly separable parameters. The GA searches for the order of the linear model (zeros and poles), the input and output nonlinearities, and the order and the interval of these nonlinearities. Meanwhile, the system identification optimizes the locations of the poles and zeros as well as the parameters of the input and output nonlinearities. The synergy between the two agents allows the entire space to be evaluated for a global solution using the heuristic search advantage of the GA coupled with the fine-tuning of the parameters using the localized search advantage of the system identification. Results show that using the GA agent expedited the search process and allowed for reaching a globally optimized model. [ABSTRACT FROM AUTHOR]

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Computational efficiency is significantly enhanced using artificial neural network-based computing. A two-terminal memristive device is a powerful electronic device that can mimic the behavior of a biological synapse in addition to storing information and performing logic operations. This work focuses on the fabrication of a memristive device that utilizes a resistive switching layer composed of polyvinyl alcohol infused with ZnO nanoparticles. By incorporating ZnO nanoparticles into the polymer film, the fabricated memristive devices exhibit functionalities that closely resemble those of biological synapses, including short-term and long-term plasticity, paired-pulse facilitation, and spike time-dependent plasticity. These findings establish the ZnO nanoparticle-polymer nanocomposite as a highly promising material for future neuromorphic systems. [ABSTRACT FROM AUTHOR]

This paper explores advanced shape control techniques for ultra-lightweight electro-actuated polymers with composite ferroelectric thin films. It begins with an overview of PVDF-TrFE film actuators used in the development of thin-shell composites, emphasizing the need to overcome constraints related to the electrode size for successful scalability. Strain generation in thin-film actuators is investigated, including conventional electrode-based methods and non-contact electron flux excitation. Numerical studies incorporate experimentally calibrated ferroelectric parameters, modeling non-contact actuation with an equivalent circuit representation. The potential distribution generated by electron flux injection highlights its potential for reducing print-through actuation issues. Additionally, the paper outlines a vision for the future of large thin-shell reflectors by integrating the discussed methods for charging ferroelectric polymer films. A hierarchical control strategy is proposed, combining macro- and micro-scale techniques to rectify shape errors in lightweight reflectors. These strategies offer the potential to enhance precision and performance in future spaceborne observation systems, benefiting space exploration and communication technologies. [ABSTRACT FROM AUTHOR]