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Exploring innovative strategies for molecular structuring of dynamic materials that combine self‐correcting intrinsic reversibility with the robustness of covalent bonds, has been a long‐standing objective from applications perspective in fields ranging from molecular engineering to nanotechnology and interfacial science. To establish dynamic covalent chemistry approaches combined with interfacial polymerization, herein, a distinct synthetic approach is reported to develop disulfide‐bridged 2D polymeric C3N3S3 triazine thin‐films by interfacial thiol‐disulfide dynamic exchange process crosslinking tritopic planar 1,3,5‐triazine‐2,4,6‐trithiol molecular tectons via intermolecular disulfide formation in the presence of I2 vapors at the air/water interface under redox condition. The resulting centimeter‐scale polymeric thin‐films are covalently cross‐linked, dynamic in nature, featuring tunable thickness (6–200 nm) and significant morphological variations are realized under the influence of varying reaction time, concentration and types of reducing agents. Notably, C3N3S3 polymer thin films exhibit a transflectance of around 99.5% in the range from 430 to 1800 nm, show high refractive indices (1.730–1.488) and optical anisotropy with uniaxial negative birefringence. The C3N3S3 free‐standing polymer thin‐films can be easily transferred to different substrates or possibly into application‐relevant forms for device fabrications, making this useful from materials application perspective. [ABSTRACT FROM AUTHOR]

Adhesive polymer films with anisotropic properties on either side have attracted tremendous interest for biomedical and engineering applications. However, developing an innovative solution that provides effective adhesion under both dry and wet conditions remains a considerable challenge. In this study, we devised a novel process for creating adhesive films by casting polydimethylsiloxane (PDMS) onto a thermoplastic polyurethane (TPU) substrate. During the curing process, the PDMS layer in contact with the TPU was lightly cross-linked, which significantly increased adhesion. The catalytic reaction used for polymerization was regulated by the TPU, which is known to adsorb metal ions. This adhesive PDMS film (APF) demonstrated outstanding adhesion on various substrates under dry and underwater conditions and maintained adhesion even after repeated use. In practical applications, the APF proved to be an effective waterproof patch by adhering to the surfaces of objects submerged in water. Adhesive polydimethylsiloxane (PDMS) film is successfully fabricated by casting process using thermoplastic polyurethane (TPU). During the curing process, the PDMS lightly cross-linked at the interface with the TPU exhibited a remarkable increase in adhesion properties. The catalytic reaction used for polymerization was regulated by the TPU, which is known to adsorb metal ions. This adhesive PDMS film (APF) demonstrated outstanding adhesion on various substrates under dry and underwater conditions and maintained adhesion even after repeated use. Our findings suggest that the APF could be used an effective waterproof patch by adhering to the surfaces of objects submerged in water. [ABSTRACT FROM AUTHOR]

In this study, various diamine monomers were used to synthesize aramid polymer films via a low-temperature solution condensation reaction with diacid chloride. For diamines with relatively high basicity, the reaction system became opaque because amine salt formation inhibited polymer synthesis. Meanwhile, low-basicity diamines with strong electron-withdrawing groups, such as CF3 and sulfone, were smoothly polymerized without amine salt formation to provide highly viscous solutions. The acid byproduct HCl generated during polymerization was removed by adding propylene oxide to the reaction vessel and converting the acid into highly volatile inert substances. The resulting solutions were used as varnishes without any additional purification, and polymer films with an excellent appearance were easily obtained through a conventional casting and convection drying process. The films neither tore nor broke when pulled or bent by hand; furthermore, even when heated up to 400 °C, they did not decompose or melt. Moreover, polymers prepared from 2,2-bis(trifluoromethyl)benzidine (TFMB) and bis(4-aminophenyl)sulfone (pAPS) did not exhibit glass transition until decomposition. The prepared polymer films showed a high elastic modulus of more than 4.1 GPa and a high tensile strength of more than 52 MPa. In particular, TFMB-, pAPS-, and 2,2-bis(4-aminophenyl)hexafluoropropane-based polymer films were colorless and transparent, with very high light transmittances of 95%, 96%, and 91%, respectively, at 420 nm and low yellow indexes of 2.4, 1.9, and 4.3, respectively. [ABSTRACT FROM AUTHOR]

Development of biobased aliphatic polyesters with better mechanical (tensile) properties in film has attracted considerable attention. This report presents the synthesis of soluble network biobased aliphatic polyesters by acyclic diene metathesis (ADMET) polymerization of bis(undec-10-enyl)isosorbide diester [M1, dianhydro-D-glucityl bis(undec-10-enoate)] in the presence of a tri-arm crosslinker [CL, glycerol tris(undec-10-enoate)] using a ruthenium–carbene catalyst, and subsequent olefin hydrogenation using RhCl(PPh3)3. The resultant polymers, after hydrogenation (expressed as HCP1) and prepared in the presence of 1.0 mol% CL, showed better tensile properties than the linear polymer (HP1) with similar molecular weight [tensile strength (elongation at break): 20.8 MPa (282%) in HP1 vs. 35.4 MPa (572%) in HCP1]. It turned out that the polymer films prepared by the addition of CL during the polymerization (expressed as a 2-step approach) showed better tensile properties. The resultant polymer film also shows better tensile properties than the conventional polyolefins such as linear high density polyethylene, polypropylene, and low density polyethylene. [ABSTRACT FROM AUTHOR]

Initiated chemical vapor deposition is a unique solvent-free and completely dry vapor-phase deposition technique used to synthesize organic polymer films. In this process, an activated initiator, monomer, and carrier gas are introduced into the reaction chamber simultaneously. This technique has been widely adopted. However, if the monomer and initiator are introduced into the chamber in stages—allowing gas-phase monomer deposition and condensation first, followed by initiator introduction and controlling the monomer partial pressure to be higher than the saturated vapor pressure—non-spherical polymer nanoparticles with dome-like shapes can be obtained. This advanced iCVD technique is referred to as the "Condensed Droplet Polymerization Approach". This high monomer partial pressure gas-phase deposition is not suitable for forming uniformly composed iCVD films; but interestingly, it can rapidly obtain polymer nanodomes (PNDs). Using CDP technology, Franklin polymerized multifunctional nanodomes in less than 45 s, demonstrating a wide range of continuous particle size variations, from sub-20 nanometers to over 1 micron. This rapid synthesis included a variety of functional polymer nanodomes in just a matter of seconds to minutes. This review discusses the crucial process conditions of the Condensed Droplet Polymerization (CDP) Approach for synthesizing PNDs. The main focus of the discussion was on the two-step method for synthesizing PNDs, where the nucleation mechanism of PNDs, factors influencing their size, and the effect of pressure on the distinct condensation of monomer vapor into polymer nanodomes and polymer films were extensively explored. [ABSTRACT FROM AUTHOR]

Thin films of p‐hexadecylstyrene (C16Sty) are prepared by an ion‐assisted deposition (IAD) and an electron‐assisted deposition (EAD) methods. The IAD enhances polymerization of C16Sty molecules by irradiating argon ions on the substrate surface, while the EAD initiates radical polymerization by irradiating electrons to the C16Sty vapor. The polymerization by these methods renders the films to be amorphous, whereas the conventional vapor deposition produces polycrystalline films consisting of C16Sty monomers. Upon thermal stress, the amorphous polymer films by IAD and EAD undergo morphological change at temperatures lower than that observed for the vapor‐deposited polycrystalline film. However, the polymer films retain smooth structure without coagulation upon heating. The deposited films have surface energy lower than that of polyethylene. Especially, the films deposited by EAD have a surface energy comparable to that of a normal alkane. The IAD and EAD of C16Sty are promising methods for preparing inert surfaces by dry processes. [ABSTRACT FROM AUTHOR]

Interfacial polymerization is a well-known process to synthesize separation layers for thin film composite membranes at an immiscible organic liquid–aqueous liquid interface. The organic–aqueous interface determines the diffusion dynamics of monomers and the chemical environment for polymerization, exerting a critical influence on the formation of polymer thin films. This review summarizes recent advances in tailoring interfacial polymerization using interfaces beyond the conventional alkane–water interface to achieve high-performance separation films with designed structures. Diverse liquid–liquid interfaces are introduced for synthesizing separation films by adding co-solvents into the organic phase and/or the aqueous phase, respectively, or by replacing one of the liquid phases with other solvents. Innovative liquid–gel and liquid–gas interfaces are then summarized for the synthesis of polymer thin films for separation. Novel strategies to form reaction interfaces, such as spray-coating, are also presented and discussed. In addition, we discuss the details of how a physically or chemically patterned substrate affects interfacial polymerization. Finally, the potential of unconventional interfaces in interfacial polymerization is forecast with both challenges and opportunities. [ABSTRACT FROM AUTHOR]

Light‐responsive surfaces are attracting increasing interest, not least because their physicochemical properties can be selectively and temporally controlled by a non‐invasive stimulus. Most existing immobilization strategies involve the chemical attachment of light‐responsive moieties to the surface, although this approach often suffers from a low surface concentration of active species or a high inhomogeneity of applied coatings. Herein, electropolymerization of carbazoles as a facile and rapid approach for preparing light‐responsive azo‐based surface coatings is presented. The electrochemical oxidative polymerization of bis‐carbazole containing azo‐monomers yields stable films, in which the photochemical properties and specific pH sensitivity of azo molecular switches are retained. Moreover, the molecular design enables electrocatalytic control over Z→E azo double bond isomerization facilitated by the conductive polycarbazole backbone. Ultimately, the high degree of control over macromolecular properties yields conductive surface coatings responsive to a range of stimuli, showing great promise as a strategy for versatile application in organic electronics. [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]

Facile and efficient synthesis of conjugated donor-acceptor polymers via direct C-H arylation polymerization has received significant interest in organic electronic applications. We report here a one-pot synthesis of a series of bis(thiophen-2-yl)benzothiadiazole-based donor-acceptor polymers P1-4 via direct C-H arylation polymerization in excellent yield. Two donor moieties [3-hexylthiophene and 1,4-bis(dodecyloxy)benzene], and one acceptor unit 4,7-bis(thiophen-2-yl)benzo[c][1,2,5]thiadiazole were used for direct C-H arylation polymerization. The prowess of the methodology was applied to synthesis of polymer by adding one donor unit followed by a second donor unit after the due course. The resulting polymers are soluble and characterized. Optical and electrochemical properties were carried out by UV-Vis-NIR and cyclic voltammetry, respectively. A temperature-dependent absorption of the polymer films blended with PC71BM was studied for photovoltaic application. Devices were fabricated by solution-processable deposition of active layer and a PCE of 3.82% was achieved. [ABSTRACT FROM AUTHOR]

Polymer brushes are densely grafted, chain end‐tethered assemblies of polymers that can be produced via surface‐initiated polymerization. Typically, this is accomplished using initiators or chain transfer agents that are covalently attached to the substrate. This manuscript reports an alternative route towards polymer brushes, which involves the use of non‐covalent cucurbit[7]uril‐adamantane host–guest interactions to surface‐immobilize initiators for atom transfer radical polymerization. These non‐covalent initiators can be used for the surface‐initiated atom transfer radical polymerization of a variety of water‐soluble methacrylate monomers to generate supramolecular polymer brushes with film thicknesses of more than 100 nm. The non‐covalent nature of the initiator also allows facile access to patterned polymer brushes, which can be produced in straightforward fashion by drop‐casting a solution of the initiator‐modified guest molecules onto a substrate that presents the cucurbit[7]uril host. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, this study reports the first direct electropolymerization of a dicyanobenzene-carbazole dye functionalized with an imidazole group to prepare redox- and photoactive porous organic polymer (POP) films in controlled amounts. The POP films were grown on indium-doped tin oxide (ITO) and carbon surfaces using a new monomer, 1-imidazole-2,4,6-tri(carbazol-9-yl)-3,5-dicyanobenzene (1, 3CzImIPN), through a simple one-step process. The structure and activities of the POP films were investigated as photoelectrodes for electrooxidations, as heterogeneous photocatalysts for photosynthetic olefin isomerizations, and for solid-state photoluminescence behavior tunable by lithium-ion concentrations in solution. The results demonstrate that the photoredox-POPs can be used as efficient photocatalysts, and they have potential applications in sensing. [ABSTRACT FROM AUTHOR]

Poly(3,4-ethylenedioxythiophene) (PEDOT) film was electrochemically prepared in nematic LC solvent under centrifugal force. Polarized ultraviolet-visible (UV-Vis) absorption spectra and polarizing optical microscopy (POM) images of the polymer film indicate orientation perpendicular to centrifugal force direction. PEDOT alignment was achieved during the polymerization through alignment of the liquid crystal matrix by centrifugal force. The monomer was polymerized along the liquid crystal alignment to form oriented PEDOT. Visualization of LC director was achieved by electrochemical polymerization in the LC. [ABSTRACT FROM AUTHOR]

All‐organic dielectric polymers with excellent capacitive energy storage capabilities have great potential applications in the fields of modern electronics and power systems. However, it is still challenging to achieve simultaneous improvements in both energy density and efficiency in these all‐organic dielectric polymers. This work proposes the all‐organic bilayer composite films with ferroelectric polymer poly(vinylidene fluoride‐hexafluoropropylene) (P(VDF‐HFP)) and linear polymer fluorene polyester (FPE) as the energy storage dielectrics for film capacitors. Compared with pure FPE films, the bilayer composite films exhibit improved dielectric constant. What is more outstanding is that the bilayer composite films has higher energy storage density and energy storage efficiency under the same electric field compared with the pure P(VDF‐HFP) film. Particularly, an outstanding Ud of 7.00 J/cm3 accompanied with great η of 95.9% has been delivered in the resulting bilayer composite films via optimizing the P(VDF‐HFP) content (22.2 vol%) at 520 kV/mm. The compatibility of the two polymers was discussed by simulating the potential distribution of the two polymer molecular chains. This work opens up a new way to prepare compatible polymer flexible capacitor films on a large scale. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polymer brush grafted films with different architectures were synthesized. • Combined method of electrodeposition and SI-PET-RAFT polymerization was employed. • Thickness, morphology, absorptivity, and electrochemistry of the films were studied. • Hyperbranched polymers exhibit compactness and ability to passivate brush gaps. • Hyperbranched polymer brushes are promising as protective thin coatings. Hyperbranched polymers, not only possess higher functionality, but are also easier to prepare compared to dendrimers and dendric polymers. Combining electrodeposition and surface-initiated photoinduced electron transfer-reversible addition-fragmentation chain transfer (SI-PET-RAFT) polymerization is hypothesized to be a novel strategy for preparing hyperbranched polymer films on conductive surfaces without degassing. Polymer brush grafted films with four different architectures (i.e. linear, branched, linear- block -branched, and branched- block -linear) were prepared on gold-coated glass substrates using electrodeposition, followed by SI-PET-RAFT polymerization. The resulting film structure and thickness, surface topology, absorption property, and electrochemical behavior were confirmed by spectroscopy, microscopy, microbalance technique, and impedance measurement. These hyperbranched polymer brushes were capable of forming a thicker but more uniformly covered films compared to linear polymer brush films, demonstrating that hyperbranched polymer films can be potentially useful for fabricating protective polymer coatings on various conductive surfaces. [ABSTRACT FROM AUTHOR]

We developed a catalyst‐free, atom‐economical interfacial amino‐yne click polymerization to in situ synthesize new aggregation‐induced emission luminogen (AIEgen)‐based free‐standing porous organic polymer films at room temperature. The crystalline properties of POP films were confirmed by powder X‐ray diffraction and high‐resolution transmission electron microscopy. The good porosity of these POP films was proved by their N2 uptake experiments. The thickness of POP films can be easily regulated from 16 nm to ≈1 μm by adjusting monomer concentration. More importantly, these AIEgen‐based POP films show bright luminescence with high absolute photoluminescent quantum yields up to 37.8 % and good chemical and thermal stability. The AIEgen‐based POP film can encapsulate an organic dye (e.g. Nile red) to further form an artificial light‐harvesting system with a large red‐shift (Δλ=141 nm), highly efficient energy‐transfer ability (ΦET=91 %), and high antenna effect (11.3). [ABSTRACT FROM AUTHOR]

A carbon–carbon-linked, ultrathin, two-dimensional (2D) polymer film was prepared at the air/water interface through photochemically triggered [2 + 2] cycloaddition. The preorganization of the monomers on the water surface and the subsequent photo-polymerization led to the successful preparation of the ultrathin 2D polymer film. The obtained film is continuous, free standing, and has a large area (over 50 μm2). Transmission electron microscopy (TEM) and atomic force microscopy (AFM) give clear evidence of the ultrathin film morphology. Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) indicate successful photo-induced [2 + 2] polymerization. [ABSTRACT FROM AUTHOR]

To create a (POT–CSA/ZnO) nanocomposite, a chemical oxidative polymerization of O-toluidine was carried out in the presence of nano ZnO. This step took place throughout the synthesis. In the attendance of hydro chloric acid (HCl) and ammonium persulfate (APS) as an oxidant and camphor solfunic acid (CSA) as a dopant, polymerization can be accomplished by using a monomer mixture with an equal molar ratio. Scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), and UV–Vis spectroscopy were utilized in the procedure of characterizing the material. The results displayed that the polymer film revealed both excitonic transition π – π and to π − π * transition. The semiconducting character of the composite can be confirmed by its electrical conductivity. [ABSTRACT FROM AUTHOR]

Linseed oil-based composite films were prepared with cinnamaldehyde (Cin) using a modified clay (organoclay) through in situ polymerization, which is the result of the interaction between Cin and organoclay. The incorporation of organoclay reduces the polymer chain's mobility and, therefore, increases the thermal stability of the composite films. In some experimental conditions, the clay is located both inside and on the surface of the film, thus, affecting the mechanical and thermal properties as well as the surface properties of the composite films. The incorporation of organoclay decreases the water contact angle of the composite film by more than 15%, whatever the amount of cinnamaldehyde. However, the incorporation of cinnamaldehyde has the opposite effect on film surface properties. Indeed, for the water vapor permeability (WVP), the effect of cinnamaldehyde on the film barrier properties is much higher in the presence of organoclay. The incorporation of hydrophobic compounds into the polymer films reduces the water content, which acts as a plasticizer and, therefore, decreases the WVP by more than 17%. Linseed oil has a natural antioxidant activity (~97%) due to the higher content of unsaturated fatty acids, and this activity increased with the amount of organoclay and cinnamaldehyde. [ABSTRACT FROM AUTHOR]

The influence of the initial composition of a CF4 + CHF3 + Ar mixture and bias power on the electrical parameters of the plasma, the composition of the gas phase, and the kinetics of heterogeneous processes on the treated surface under conditions of an induction RF (13.56 MHz) discharge is studied. It is found that the variation of the CF4/CHF3 ratio does not lead to significant perturbations of the parameters of the electronic and ionic components of the plasma, but significantly changes the concentrations of fluorine atoms and polymer-forming radicals. In contrast, an increase in the bias power at a fixed initial composition of the mixture has practically no effect on the concentrations of active particles, but is characterized by a proportional change in the energy of the bombarding ions. The model analysis of the kinetics of heterogeneous processes shows that the CF4/CHF3 ratio provides wider ranges of regulation of the etching rate of the base material, as well as the deposition rate of the fluorocarbon polymer film and its thickness. [ABSTRACT FROM AUTHOR]

The current study presents the principle of a new approach to fabricating redox-active polymers film on mesoporous TiO2 electrodes. This new strategy involves the top-down approach (adsorption) combined with bottom-up layer-by-layer (LbL) crosslinking and "in situ" co-polymerization reactions. This approach uses 4,40-bipyridinium units, so-called viologen with an anchoring phosphono ethyl acid and the vinyl group as building blocks molecules, and 1,3,5-tris-(bromomethyl) benzene as crosslinker. Crosslinking and co-polymerization reactions lead to the growth of the concentration of redox species on the surface and increased stability of the colored areas towards forced desorption in water. The method offers a simple, versatile way to manufacture nanostructured functional materials. [ABSTRACT FROM AUTHOR]

Developing high-efficient visible light macromolecular photoinitiator (macro PI) with excellent initiation performance, low migration, high biosafety and multi-function is beneficial to broaden the application of photopolymer. Lignin contains chromophores which could generate free radicals under light irradiation. In this study, a lignin-based polymerizable macro PI (DAL-11ene-amine) was designed and synthesized through covalent grafting 10-undecenoyl chloride (11ene) and hydrogen donor 4-(dimethylaminobenzoic acid) ethyl ester (EDAB) into dealkaline lignin (DAL) skeleton. The structure of DAL-11ene-amine was characterized by UV–vis, FTIR, 1H NMR, GPC, and 31P NMR spectra. Under the irradiation of a 405 nm LED, DAL-11ene-amine can directly produce active species and initiate the polymerization of acrylate monomers or thiol-ene click reaction. The photoinitiation efficiency of DAL-11ene-amine is higher than that of DAL-11ene or the two-component combination of DAL-11ene and EDAB. Using DAL-11ene-amine as PI, the prepared polymer films exhibit excellent UV-blocking property. With only 0.5 wt% addition of DAL-11ene-amine, nearly 100% of UVB + UVC and the most of UVA can be blocked by the films. Moreover, DAL-11ene-amine exhibits higher migration stability and biosafety because it can be covalently linked into polymer cross-linking networks. The results indicate that DAL-11ene-amine has great application potentials in preparing environmentally friendly UV-blocking films and biosafety coatings. [ABSTRACT FROM AUTHOR]

• Thin films from fluorinated paracyclophane dimers were prepared via vapor phase. • The growth yield for polymer films per dimer is 0.9∼2.1 nm/mg. • These polymeric films show good uniformity with under 3 nm of roughness. • Polymeric thin films with different surface hydrophilicity can be delivered. Poly(para-xylylene) thin films from Gorham method via chemical vapor polymerization (CVP) process (so called Parylene) have been extensively utilized in various application fields. Specific functional groups can be also introduced into thin polymeric films via CVP process using functionalized paracyclophane dimer. There have been numerous efforts to fabricate parylene thin films using synthesized and functionalized paracyclophane dimers so far. Herein we report on synthesis of fluorine containing paracyclophane dimers and their polymeric thin films via Gorham method. Three different types of fluorine containing paracyclophane derivatives are synthesized and the CVP thin films are prepared in all cases by adjusting processing condition. Even though the functional groups on parylene thin films are similar, dramatic differences in surface energy can be observed. This work can provide extended material choices for whom want to precisely control surface properties with robust, pin-hole free, and conformal coatable polymeric thin films. [ABSTRACT FROM AUTHOR]

The growth mechanism of linear chain polymerization by vapor deposition was investigated based on dynamic scaling analysis of atomic force microscopy images of parylene-C films grown simultaneously on liquid and solid substrates. These controlled experiment allow us to identify the role of fourth order surface diffusion driven by chemical potential gradient (or the local curvature) of interface even in the presence of nonlocal effects due to bond limitations during linear chain polymerization. The average global slope of surface structures evolved along different paths on different substrates overlaps and remains the same at film thickness above 200 nm, where the film growth rate stabilizes, reaching a "terminal topography". Terminal topography, a coarse-grained representation of the surface structure, occurs independently of parylene type and growth conditions and is an inherent property of linear chain polymer films grown by vapor deposition polymerization. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, polymer-dispersed liquid crystal (PDLC) films of acrylate polymer systems were fabricated by polymerization-induced phase separation. It was a complex process involving simultaneous curing and phase separation to form nematic microdomains. We also have examined the morphology of PDLC films, which show great potential for electro-optic applications. Here we used the adsorbability of white carbon black and loaded the photoinitiator (IRG651) in it to prepare PDLC films. Electrooptic devices based on the PDLC films were constructed by using indium-tin-oxide transparent electrodes, and the electro-optic responsivity was also explored. [ABSTRACT FROM AUTHOR]

The properties of the final product resulting from plasma polymerization strongly depend on the operating conditions and they impact the final application of the plasma polymer coating. Low‐pressure pulsed plasma polymerization of maleic anhydride was investigated at two different positions in relation to the glow discharge in a 1‐m‐long tubular reactor. Interestingly, competition was observed in the deposition of maleic anhydride plasma polymer in the form of a smooth thin film versus that in the form of nanoparticles. The possibility of a spatiotemporal control of plasma polymerization enabled the deposition of a plasma coating with tunable morphological properties depending on the sample position from the glow discharge and on the plasma pulse parameters (on‐time and off‐time). [ABSTRACT FROM AUTHOR]

Copper (1) oxide nanoparticles together with matrix polymers of polyvinyl alcohol (PVA) and polyaniline (PANI) composite films were synthesized, as these materials are of importance in optoelectronic applications. Nanoparticles of Cu2O were produced by chemical precipitation. Polymerization of aniline was carried out through polymerization in an acidic medium. Structural, thermal, and optical properties of PVA+PANI/Cu2O nanocomposite were inspected by x-ray diffraction (XRD), scanning electron microscopy (SEM), fourier-transform infrared (FTIR), differential scanning calorimeter (DSC) and ultraviolet-visible spectroscopy (UVVis spectroscopy). X-ray diffraction peaks at 29.53°, 36.34°, and 42.22° indicated the presence of cuprous oxide nanoparticles, having high dispersions and limited size distributions. The estimated average size of Cu2O nanoparticles was ~ 17.1525 nm. A characteristic ‎peak‎ at‎ around ‎2θ‎=‎18.5°‎was attributed to periodical parallel and perpendicular polymer chains, which denoted the formation of PANI. SEM results indicated the symmetrical dispersion of Cu2O nanoparticles inside the hybrid polymer of PVA and PANI matrix, being potentially useful for encapsulation and acting as a good capping agent. FTIR results established the formation of PANI and Cu2O with nanocrystalline nature. DSC results revealed the appearance of one single peak of Tg which decreased with Cu2O content of 4% wt, followed by an increase of that value by increasing Cu2O content up to 16%wt. Thermogram analysis of the PANI and PVA embedded with Cu2O form showed an exothermic peak at (240- 292)℃ affiliated to the cross-linking reaction, while the Tm value of prepared nanocomposites is just about close to that of PVA polymer. The results indicated that there is an increase in thermal stability due to the presence of Cu2O NPS within the matrix of polymers. The distinguishing peaks at 330, 347, and 457 nm which refer to PANI are assigned to π−π* electron transitions among the benzenoid rings. The high absorption intensity of the peak at 470 nm for the blended PVA+PANI having 12% wt of Cu2O NPS is assigned due to the inter-band transitions for electrons of the core copper as well as copper oxide. This points out that the increasing quantity of Cu2O NPs leads to increases in the amounts of highly oxidized structures in PANI and decreases in the doping electrons and length of conjugation throughout the incorporation of Cu2O NPs into PANI matrix. Depending on the practical results, it can be said that these polymeric nanocomposites can be efficiently used in photovoltaic technology applications. [ABSTRACT FROM AUTHOR]

In this work, we performed the comparative study of plasma parameters, steady-state gas phase compositions and Si reactive-ion etching kinetics in CF4 + O2 + Ar, CHF3 + O2 + Ar and C4F8 + O2 + Ar gas mixtures with variable O2/Ar component ratios. It was found that the substitution of Ar for O2 (a) did not disturb the well-known correlation between the polymerizing ability and the F/C ratio in the original fluorocarbon molecule; (b) causes similar changes in electrons- and ions-related plasma parameters (electron temperature, plasma density, ion bombardment energy); and (c) always suppresses densities of polymerizing radicals and reduces the polymer film thickness. At the same time, the specific effects of oxygen on F atom kinetics result in sufficient differences in their densities and fluxes. It was shown that the dominant etching mechanism for Si in all three gas systems is the chemical etching pathway provided by F atoms (since the contribution of physical sputtering is below 10%) while measured etching rates do not follow the behavior of F atom flux. The phenomenological analysis of heterogeneous process kinetics allowed one to suggest factors influencing the effective reaction probability. These are either the transport of F atoms through thick polymer film (in the case of high-polymerizing C4F8 + O2 + Ar plasma) or heterogeneous reactions with a participation of oxygen atoms under the condition of thin or non-continuous polymer film (in the case of low-polymerizing CF4 + O2 + Ar plasma). [ABSTRACT FROM AUTHOR]

In this work, thermal and mechanical properties of cationic cassava starch-g-poly(butyl acrylate-co-methyl methacrylate) films with different amounts of cationic cassava starch (CCS) were studied. The objective of this work was to substitute a portion the monomers (BA/MMA) by CCS in the copolymer and to investigate the consequent effects on the properties of the polymer latex films (e.g., graft percentage, surface tension, thermal and mechanical properties). The results show that the grafting percentage decreased as the concentration of CCS increased. Thermal and mechanical properties of polymer films showed a direct relationship with respect to the content of CCS used and the grafting percentage. Higher grafting percentage led to improvement of the thermal degradation, which indicated better thermal stability than neat poly(BA/MMA). DSC analysis showed that the Tg of the graft copolymers was a little lower as compared to Tg values of un-grafted copolymers. The addition of CCS increases the tensile, elastic modulus and hardness properties of the polymer film, but the elongation at break decreased dramatically. The optimal CCS contents that maximized not only thermal properties, but also mechanical properties, were 7 and 10 mass%, which are directly related to the grafting percentage and CCS content in the formulation. In addition, these results create a new approach for the application of CCS graft-polymer as an adhesive for wood, paper and shoes insole applications. [ABSTRACT FROM AUTHOR]

Biofilms are a persistent issue in healthcare and industry. Once formed, the eradication of biofilms is challenging as the extracellular polymeric matrix provides protection against harsh environmental conditions and physically enhances resistance to antimicrobials. The fabrication of polymer brush coatings provides a versatile approach to modify the surface to resist the formation of biofilms. Herein, the authors report a facile synthetic route for the preparation of surface‐tethered polymeric brushes with antifouling and visible light activated bactericidal properties using surface‐initiated photoinduced electron transfer‐reversible addition‐fragmentation chain transfer polymerization (SI‐PET‐RAFT). Bactericidal property via the generation of singlet oxygen, which can be temporally and spatially controlled, is investigated against both Gram‐positive and Gram‐negative bacteria. In addition, the antibacterial properties of the surface can be recycled. This work paves the way for the preparation of polymer films that can resist and kill bacterial biofilms [ABSTRACT FROM AUTHOR]

Considering the significant synthetic efforts for the preparation of poly(3,4-ethylenedioxythiophene) (PEDOT) and its soluble derivatives, very little is known about poly(3,4-ethylenedioxyselenophene) (PEDOS), especially for soluble polymers. Here, we report the synthesis of soluble dodecyl-substituted poly(3,4-ethylenedioxyselenophene) (PEDOS-C12) by two different chemical polymerization methods- transition metal-mediated and Grignard metathesis (GRIM). The polymer PEDOS-C12 prepared by GRIM was characterized using NMR, gel permeation chromatography, UV–vis-NIR spectroscopy, cyclic voltammetry and shows high conductivity. The obtained neutral polymer PEDOS-C12 (hydrazine-dedoped) prepared by GRIM was used for spray processable electrochromic property and organic solar cells. The optical contrast ratio and coloration efficiency of the polymer film were found to be 20.8% and 131.9 cm2/C at 770 nm. The photovoltaic device was fabricated using solution-processable PEDOS-C12 as hole transport layer (HTL) with the simple geometry ITO/PEDOS-C12(HTL)/P3HT:PC61BM/Al and achieved a power conversion efficiency up to ~ 0.52% under ambient conditions. [ABSTRACT FROM AUTHOR]

Polymerization at the liquid–liquid interface has attracted much attention for synthesizing ultrathin polymer films for molecular sieving. However, it remains a major challenge to conduct this process outside the alkane–water interface since it not only suffers water‐caused side reactions but also is limited to water‐soluble monomers. Here, we report the interfacial polymerization at the alkane/ionic liquid interface (IP@AILI) where the ionic liquid acts as the universal solvent for diversified amines to synthesize task‐specific polyamide nanofilms. We propose that IP@AILI occurs when acyl chloride diffuses from the alkane into the ionic liquid instead of being triggered by the diffusion of amines as in the conventional alkane–water system, which is demonstrated by thermodynamic partitioning and kinetic monitoring. The prepared polyamide nanofilms with precisely adjustable pore sizes display unprecedented permeability and selectivity in various separation processes. [ABSTRACT FROM AUTHOR]

Gyroid‐nanostructured all‐solid polymer films with exceedingly high proton conductivity and low H2 gas permeability have been created via crosslinking polymerization of mixtures of a zwitterionic amphiphilic monomer and a polymerizable imide‐type acid that co‐organize into bicontinuous cubic liquid‐crystalline phases. The gyroid nanostructures are visualized by reconstructing a 3D electron map from the synchrotron X‐ray diffraction patterns. These films exhibit high proton conductivity of the order of 10−1 S cm−1 and extremely low H2 gas permeability of the order of 10−15 mol m m−2 s−1 Pa−1. These properties can be ascribed to the presence of the ionic liquid‐like layer along the gyroid minimal surface. Since these two characteristics are required for improving the performance of proton‐exchange membrane fuel cells, the present membrane design represents a promising strategy for the development of advanced devices, pertinent to establishing sustainable energy sources. [ABSTRACT FROM AUTHOR]

[Display omitted] • Linear, Y- and Ψ-shaped PMMA and PDMAEMA brushes have been prepared via SI-ATRP. • The architecture of the polymer brushes has an influence on the swelling behavior. • The introduction of branching results in an increase in the rate constant of degrafting. A series of 3 homologous surface-anchored initiators for atom transfer radical polymerization has been used to graft linear, Y- and Ψ-shaped poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(methyl methacrylate) (PMMA) brushes from silicon surfaces. The film thicknesses of these architecturally different polymer brushes could be tuned both by controlling the polymerization time, as well as (as was shown for the polymerization of 2-(dimethylamino)ethyl methacrylate) by changing the monomer concentration. The library of linear, Y- and Ψ-shaped PDMAEMA and PMMA brushes was used to investigate the possible impact of polymer architecture on the swelling properties as well as the degrafting behavior of these surface-grown polymer films. The swelling of the PDMAEMA and PMMA brushes in PBS, respectively, acetone as a solvent was studied by ellipsometry. These experiments revealed a smaller swelling ratio for Y-shaped polymer brushes, as compared to linear analogues of comparable dry film thickness. Degrafting experiments were conducted with linear, Y- and Ψ-shaped PDMAEMA brushes in PBS. These experiments revealed a 2-fold, respectively, 3-fold increase in the initial rate constant of degrafting for the Y- and Ψ-shaped PDMAEMA brushes as compared to the linear analogues. [ABSTRACT FROM AUTHOR]

[Display omitted] • A 3D view in plasma polymerization is crucial for coating functional materials. • HMDSO yields plasma film-forming species with different sticking probabilities. • Surface oxidation is relevant in plasma polymerization for complex geometries. Hexamethyldisiloxane (HMDSO) low-pressure plasmas are known for their versatility in the deposition of plasma polymer films (PPFs) with different properties and applications. Although they have been studied for decades, the reaction mechanisms of plasma polymer formation leave open questions, particularly when deposition on 3D materials with complex geometries such as cavities and undercuts is considered. In the present study, two configurations named "cavity" and "undercut" have been selected to study the influence of diffusion of film-forming species and surface reactivity in HMDSO plasmas without and with O 2 admixture. A varying spatial chemical composition of the plasma polymer deposit along the penetration depth of the studied configurations indicates different sticking probabilities of the film-forming species. Furthermore, although ion-induced effects are usually only considered for direct plasma exposure, the obtained results and additional etching experiments reveal that the contribution of high-energy particles might still be considered underneath small openings. Finally, the relevance of oxidizing chemical reactions at the surface inside the configurations is clarified when O 2 is added to the plasma. [ABSTRACT FROM AUTHOR]

Single-particle fluorescence imaging is used to monitor dynamic processes that occur during patterned photopolymerization of liquid-crystalline monomers. A spatial gradient of chemical potential can be created at the border of bright and dark regions by structured illumination in the photopolymerization process, leading to mutual diffusion of polymers and monomers. Analysis of the fluorescence from single quantum dots doped into the monomers at minute concentrations enables visualization of highly directional flow from the illuminated region where the photopolymerization proceeds toward a masked unpolymerized region. This directional mass flow causes flow-induced orientation of the polymers that is subsequently fixed by completion of the polymerization reaction, resulting in a mesoscopic aligned area of the polymer film. Polymerization: Bringing molecules into line The light-induced processes that enable the alignment of long molecules have been described by scientists in Japan. The long chain of molecules that form a polymer is often tangled and disorganized. However, in so-called liquid-crystalline polymers, the molecular chains are straight. Aligning these chains with each other creates materials useful for photonic and biomedical applications. Current alignment techniques are slow and complex or require the addition of a dye, which alters the material's properties. Martin Vacha and Atsushi Shishido from the Tokyo Institute of Technology (in Tokyo and Yokohama) and co-workers used single-particle fluorescence imaging to understand the molecular processes that occur during patterned photopolymerization, a novel method for aligning liquid-crystalline polymers which avoids the disadvantages above. They show that optical illumination induces chemical differences between the bright and shadowed regions, which helps alignment. Single-particle fluorescence imaging is used to monitor dynamic processes that occur during patterned photopolymerization of liquid-crystalline monomers. Spatial gradient of chemical potential created at the border of bright and dark regions by structured illumination leads to mutual diffusion of polymers and monomers. Fluorescence of single quantum dots doped into the monomers visualizes highly directional mass flow from the illuminated region where the photopolymerization proceeds toward a masked unpolymerized region. The flow-induced orientation of the polymers is subsequently fixed by completion of the polymerization reaction, resulting in a mesoscopic aligned area of the polymer film. [ABSTRACT FROM AUTHOR]

The reproducibility of polymer brush synthesis via surface‐initiated controlled radical polymerization is interrogated. Experiments compare the stability of initiating monolayers for surface‐initiated (SI) reversible addition‐fragmentation chain transfer polymerization (SI‐RAFT) and SI atom transfer radical polymerization (SI‐ATRP). Initiator‐functionalized substrates are stored under various conditions and grafting densities of the resulting polymer brush films are determined via in situ ellipsometry. Decomposition of one of the examined SI‐RAFT initiators results in limited reproducibility for polymer brush surface modification. In contrast, initiators for SI‐ATRP show excellent stability and reproducibility. While both techniques bring inherent benefits and limitations, the described findings will help scientists choose the most efficient technique for their goals in chemical and topographical surface modification. [ABSTRACT FROM AUTHOR]

In this work, a series of liquid crystal molecules containing cyano-phenyl-ester was designed and synthesised. Subsequently, a novel cyano-phenyl-ester liquid crystals (CPE-LCs) with a wide temperature range from −30°C to 96.4°C were developed by mixturing these liquid crystal compositions. Then as the host materials, the CPE-LCs were used for preparing polymer-dispersed and polymer-stabilised cholesteric liquid crystals (PD&SCLC) composite films by a stepwise polymerisation. The morphologies and electro-optical properties of the as-made composite films were systematically investigated through varying the acrylate liquid crystalline polymerisable monomers content, chiral doping R1011 content, applied electric field intensity and polymerisation time. Indeed, the formation of homeotropically aligned anisotropic polymer networks (HAAPNs) enabled to reduce the driving voltage of PD&SCLC from 86.6 V to 22.2 V with a reasonable contrast ratio. This work provides a new method to optimise PD&SCLC composite films in terms of the host liquid crystals. [ABSTRACT FROM AUTHOR]

The bioinspired diblock copolymers poly(pentadecalactone)‐block‐poly(2‐(2‐hydroxyethoxy)benzoate) (PPDL‐block‐P2HEB) are synthesized from pentadecalactone and dihydro‐5H‐1,4‐benzodioxepin‐5‐one (2,3‐DHB). No transesterification between the blocks is observed. In a sequential approach, PPDL obtained by ring‐opening polymerization (ROP) is used to initiate 2,3‐DHB. Here, the molar mass Mn of the P2HEB block is limited. In a modular approach, end‐functionalized PPDL and P2HEB are obtained separately by ROP with functional initiators, and connected by 1,3‐dipolar Huisgen reaction ("click‐chemistry"). Block copolymer compositions from 85:15 mass percent to 28:72 mass percent (PPDL:P2HEB) are synthesized, with Mn of from about 30 000–50 000 g mol−1. The structure of the block copolymer is confirmed by proton NMR, Fourier‐transform infrared spectroscopy, and gel permeation chromatography. Morphological studies by atomic force microscopy (AFM) further confirms the block copolymer structure, while quantitative nanomechanical AFM measurements reveal that the Derjaguin–Muller–Toporov moduli of the block copolymers range between 17.2 ± 1.8 and 62.3 ± 5.7 MPa, i.e., between the values of the parent P2HEB and PPDL homopolymers (7.6 ± 1.4 and 801 ± 42 MPa, respectively). Differential scanning calorimetry shows that the thermal properties of the homopolymers are retained by each of the copolymer blocks (melting temperature 90 °C, glass transition temperature 36 °C). [ABSTRACT FROM AUTHOR]

A bioinspired diblock copolymer is synthesized from pentadecalactone and 3‐hydroxy cinnamic acid. Poly(pentadecalactone) (PPDL) with a molar mass of up to 43 000 g mol−1 is obtained by ring‐opening polymerization initiated by propargyl alcohol. Poly(3‐hydroxycinnamate) (P3HCA) is obtained by polycondensation and end‐functionalized with 3‐azido propanol. The two functionalized homopolymers are connected via 1,3‐dipolar Huisgen addition to yield the block copolymer PPDL‐triazole‐P3HCA. The structure of the block copolymer is confirmed by proton NMR, FTIR spectroscopy and GPC. By analyzing the morphology of polymer films made from the homopolymers, from a 1:1 homopolymer blend, and from the PPDL‐triazole‐P3HCA block copolymer, clearly distinct micro‐ and nanostructures are revealed. Quantitative nanomechanical measurements reveal that the block copolymer PPDL‐triazole‐P3HCA has a DMT modulus of 22.3 ± 2.7 MPa, which is lower than that of the PPDL homopolymer (801 ± 42 MPa), yet significantly higher than that of the P3HCA homopolymer (1.77 ± 0.63 MPa). Thermal analytics show that the melting point of PPDL‐triazole‐P3HCA is similar to PPDL (89–90 °C), while it has a glass transition temperature similar to P3HCA (123–124 °C). Thus, the semicrystalline, potentially degradable all‐polyester block copolymer PPDL‐triazole‐P3HCA combines the thermal properties of either homopolymer, and has an intermediate elastic modulus. [ABSTRACT FROM AUTHOR]

The structure and properties of polymer film are greatly affected by the patterns on its surface arising from solution convection. Therefore, it is necessary to explore more detail mechanism of pattern formation. Herein, we have successfully designed variable patterns on the surface of cellulose films via roller coating method. The cellulose with three degrees of polymerization was used as raw material, and a solution of N,N-dimethyl-acetamide/lithium chloride (DMAc-LiCl) was selected as the solvent system. The pattern variations were controlled by the solution viscosity, which was affected by the degree of polymerization of cellulose, concentration and temperature of solution. The formation process of the pattern on cellulose film was in situ tracked by video recording with the help of carbon black tracker. It was found that the solution moved from the edge of the cell pattern to the center at a relatively lower viscosity (η < 8.06 Pa s), and finally formed a polygon pattern with the convex center. With the increasing of the solution viscosity (η ≥ 8.06 Pa s), the direction of its convection was completely opposite and a circular or circular-like combination pattern with concave center appeared on the surface of the cellulose film. The higher the viscosity, the larger the concave area. Moreover, the film with polygon pattern demonstrated excellent mechanical properties, and also exhibited a potential anti-counterfeiting value. These results could provide guidance in perfecting the theory of polymer fluid, and regulating the structure and properties of polymer products. [ABSTRACT FROM AUTHOR]

Herein, hydrophilic encapsulation of reduced graphite oxide (r-GO) was achieved by admicellar polymerization. Functional polymer thin films were coated on the r-GO surface for enhancing the water dispersion of r-GO. The morphology was observed by TEM and SEM. Moreover, a PHEMA thin film was coated on the surface of r-GO by admicellar polymerization using a surfactant at low concentration. The percentage of the film coated on r-GO was calculated to be 40 wt% by thermal analysis. FT-Raman has been applied to illustrate that admicellar polymerization is a nondestructive functionalization method. The water contact angles decreased from 105° to 63° after admicellar polymerization; this indicated the successful hydrophilic encapsulation of r-GO. Moreover, r-GO/PHEMA-modified glassy carbon (r-GO/PHEMA/GC) functioned well as an electrochemical biosensor for the detection of hemopexin-like domain of matrix metalloproteinase 14 (PEX-14). [ABSTRACT FROM AUTHOR]

Abstract—The thermal polymerization of styrene sorbed from the gas-phase into polymer films of polyvinylidene fluoride (PVDF) is carried out at 110°С. By this method, the "matrix‑polystyrene" composites containing up to 70 wt % polystyrene (PS), which serve as precursors of ion-exchange membranes, are synthesized. Sulfonation of grafted PS produces ion-exchange membranes with the exchange capacitance of 1–2.7 mmol/g and the protonic conductivity reaching 20–200 mS/cm when saturated with water at 25°С. The conductivity values indicate that the nonuniformity of PS distribution over film-matrix cross-section usually encountered when monomer sorbed from the gas phase is polymerized does not exert any noticeable effect on the conduction properties of sulfonated composites. The developed method of preparing composites "polymer matrix‑grafted polystyrene" substantially simplifies the synthesis of the precursor of ion-exchange membranes, decreases the necessary amount of reagents, and considerably enhances the safety of synthesis. [ABSTRACT FROM AUTHOR]

Stimuli-responsive fluorescence switching is of great importance to fluorescence modulation in a wide range of applications, such as sensors, bioimaging, and displays. We report here multi-stimuli-responsive fluorescence switching behavior of a multifunctional polymer bearing oligoaniline, azobenzene, and fluorene groups synthesized via copolycondensation polymerization. This fascinating fluorescence switching behavior is originated from controlled conformational (oligoaniline) and geometric (cis↔trans of azobenzene) changes within a polymer chain upon multiple external stimuli, including potential, pH value, redox species, UV/vis irradiation and heat. This work may provide additional avenue for tuning fluorescent properties of multifunctional polymers. We report synthesis of a multifunctional polymer bearing oligoaniline, azobenzene and fluorene units. The resulting polymer film exhibits fascinating multi-stimuli-responsive fluorescence switching performance upon multiple external stimuli, such as pH value, redox species, potentials, UV/vis light, and UV/heat stimuli. Image 1 • A polymer bearing oligoaniline, azobenzene and fluorene units was prepared. • The polymer exhibits multi-stimuli-responsive fluorescence switching behavior. • Multiple external stimuli have been applied on the resulting polymer film. [ABSTRACT FROM AUTHOR]

Two bilayer polymer films (pTPAT/pPHT and pPHT/pTPAT), derived from two star-shaped thiophene derivatives (TPAT and PHT) with central cores of triphenylamine and phenyl respectively, were successfully fabricated on ITO-glasses by electrochemical polymerization. The difference between the two bilayer polymer films pTPAT/pPHT and pPHT/pTPAT is just the layer configuration due to different sequential deposit orders of the pPHT and pTPAT layers during the electrochemical polymerization process. In the systems of bilayer films, the pPHT layer shows no electrochromism, a low HOMO level and a high impedance value, while the pTPAT layer shows obvious electrochromism, a high HOMO level and a low impedance value in contrast. The electrochromic properties showed that the optical contrast and cyclic stability of bilayer films are similar to those of the single pTPAT films, while the switching rate is relatively slower. Furthermore, in comparison with the pTPAT film, a higher ion-diffusion resistance was found in the bilayer film pTPAT/pPHT, and an obvious interface resistance was observed in the bilayer film pPHT/pTPAT. The existence of the pPHT layer in bilayer films may serve as a charge transport barrier and hinder the ion-diffusion or hole-injection process, depending on the layer structural arrangement in bilayer films. The investigation of the electrochromic properties of two bilayer films also provides unambiguous evidence for a fact that both ion-diffusion and charge-injection processes exerted great influences on the electrochromic switching rate of a polymer. [ABSTRACT FROM AUTHOR]

Spatio-temporally controlled drug release based on conducting polymer films offers a powerful technology to improve the tissue integration for implantable neuroprobes. We here explore the release efficiency of such systems in order to improve the understanding of the release mechanism and allow for optimized implementation of this technology into future drug release applications. By exposing drug loaded PEDOT coatings of different thicknesses to a multitude of release signals, along with optimizing the steps during the polymer synthesis, we could identify a highly reproducible electrostatically controlled drug release next to a slow diffusion driven release component. The release efficiency was moreover observed to be higher for a cyclic voltammetry signal in comparison to release driven by a constant potential. Biphasic current pulses, as used during neural stimulation, did not allow for long enough diffusion times to yield efficient active drug expulsion from the polymer films. A quantitative analysis could confirm an overall linear dependency between drug release and film thickness. The amount of drug released in response to the trigger signals was however not linearly correlated with the amount of charge applied. By combining these findings we could develop a model which accurately describes the drug release mechanism from a PEDOT film. The proposed model thereby points the way for how actively controlled, and diffusion related, release can be tuned for obtaining delivery dynamics tailored to specific applications. Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract Materials in direct contact with food should be monitored for the presence of species able to migrate into food. A direct method based on liquid extraction surface analysis nanoelectrospray mass spectrometry (LESA-nanoESI-MS) was developed for the analysis of the migrating species from a polymer film. Different types of molecules: post-polymerization residues, degradation products (oligomers resulting from polymer recycling, products of polymer oxidative degradation) and anti-oxidant additives (vitamin E) were demonstrated to be detected and identified, and determined quantitatively if relevant calibration standards are available. The method was validated by a comparison a standard method based on with bulk extraction mass spectrometry. It offers considerable advantages over the latter in terms of drastically reduced analysis time and solvent consumption. Also, LESA-nanoESI-MS produced simpler spectra (limited to compounds able to migrate into food) than Direct Analysis in Real Time (DART). Graphical abstract Image 1 Highlights • Method to evaluate the safety and functionalization of polymer food packings. • fast, eco-friendly and highly reproducible analysis with no sample preparation. • Possibility of quantitative monitoring of the quality of "intelligent" packings. [ABSTRACT FROM AUTHOR]

Abstract In this work, we demonstrate that an ultra-thin film of polythiophene deposited interfacially via hole-induced polymerization on the surface of dye-sensitized TiO 2 nanotube array acts as co-sensitizer, and hinders back-electron transfer in a DSSC. Consequently, the dark current, and the recombination reactions can be suppressed, leading to an improved number of electron density at the TiO 2 array electrode. Thus, an enhanced photocurrent, and power conversion efficiency of the device is achieved. This logical concept is experimentally justified, and the device, after polythiophene interfacial treatment, demonstrates an enhanced power conversion efficiency by the factor of 39.19%. Graphical abstract Image 1 Highlights • Deposition of ultra-thin polythiophene film on dye-sensitized TiO 2 nanotube array. • TiO 2 is co-sensitized, and back electron injections are hindered. • This leads to the reduction of recombination events. • Consequently, J sc and power conversion efficiency of the device are enhanced. [ABSTRACT FROM AUTHOR]

A novel conjugated polymer PProDOT(MeEO)2 based on dioxythiophene with symmetric double ethoxymethyl pendant groups was successfully synthesized through electrochemical polymerization. The polymer film exhibits reversible electrochromism switching between broadly absorbing bluish black neutral state (− 0.1 V) and transmissive sky blue oxidized state (0.7 V). The symmetric double short-chain ethoxymethyl substitution pattern was utilized to realize the broadly absorbing bluish black neutral state of the polymer film. The electrochemical, spectroelectrochemical, and electrochromic switching properties of the polymer film were studied in detail. [ABSTRACT FROM AUTHOR]

The electrooxidative polymerization of pyrrole on the surface of a glassy carbon electrode was studied, while varying the solvent, the type and concentration of supporting electrolyte, redox mediator addition to the polymerization medium, and hydrodynamic conditions. The efficiency of polymerization was determined as the ratio of the charge of the redox response of the polymer film under the standard conditions to the total charge of film formation in the monomer solution. The above factors were varied to determine the conditions that allow minimization of the ratio in order to obtain the highest yield of the polymer product. This was achieved by using a combination of a redox mediator addition with active stirring of solution. [ABSTRACT FROM AUTHOR]