Understanding how to tune the properties of electroactive materials is a key parameter for their applications in energy storage systems. This work presents a comprehensive study in tailoring polyaniline (PANI) suspensions by acid-assisted polymerization method and their subsequent deposition on boron-doped diamond (BDD) supports with low/high B concentrations. The porous or densely packed morphology of PANI is successfully controlled by varying the monomer-to-initiator ratio.
View Article and Find Full Text PDFBackground: The diagnosis of joint replacement infection is a difficult clinical challenge that often occurs when the implant cannot be salvaged. We hypothesize that the pH value of synovial fluid could be an important indicator of the inflammatory status of the joint. However, in the literature, there is a lack of data on the pH changes in hip and knee joint replacements and their relation to infection and implant failure.
View Article and Find Full Text PDFA new method for the preparation of polyaniline (PANI) films that have a 2D structure and can record high active mass loading (up to 30 mg cm) via acid-assisted polymerization in the presence of concentrated formic acid was developed. This new approach represents a simple reaction pathway that proceeds quickly at room temperature in quantitative isolated yield with the absence of any byproducts and leads to the formation of a stable suspension that can be stored for a prolonged time without sedimentation. The observed stability was explained by two factors: (a) the small size of the obtained rod-like particles (50 nm) and (b) the change of the surface of colloidal PANI particles to a positively charged form by protonation with concentrated formic acid.
View Article and Find Full Text PDFConducting polymer polyelectrolyte microspheres are typically composed of a cationic conducting polymer and an anionic polymer. The polymer chains inside these microspheres are physically or chemically cross-linked, creating a network that enables high water retention. Poly(3,4-ethylenedioxythiophene) (PEDOT) being an electrically conductive polymer exhibits a high conductivity and has great biotechnological applications.
View Article and Find Full Text PDFA new synthetic method for the fabrication of a sensing layer is presented. PANI films as an ion-to-electron transducer were prepared acid-assisted polymerization in concentrated formic acid (HCOOH) in the presence of ethanol and ammonium persulfate (APS, as the initiator). The ratio of monomer to ammonium persulfate was 1 : 0.
View Article and Find Full Text PDFConductive hydrogels are polymeric materials that are promising for bioelectronic applications. In the present study, a complex based on sulfonic cryogels and poly(3,4-ethylenedioxythiophene) (PEDOT) was investigated as an example of a conductive hydrogel. Preparation of polyacrylate cryogels of various morphologies was carried out by cryotropic gelation of 3-sulfopropyl methacrylate and sulfobetaine methacrylate in the presence of functional comonomers (2-hydroxyethyl methacrylate and vinyl acetate).
View Article and Find Full Text PDFWe constructed a sensor for the determination of Fe and/or Fe ions that consists of a polyaniline layer as an ion-to-electron transducer; on top of it, chelating molecules are deposited (which can selectively chelate specific ions) and protected with a non-biofouling poly(2-methyl-2-oxazoline)s layer. We have shown that our potentiometric sensing layers show a rapid response to the presence of Fe or Fe ions, do not experience interference with other ions (such as Cu), and work in a biological environment in the presence of bovine serum albumin (as a model serum protein). The sensing layers detect iron ions in the concentration range from 5 nM to 50 µM.
View Article and Find Full Text PDFHighly hydrophobic perfluorinated polyaniline thin films with water contact angle of ∼140° and low internal resistance properties are prepared through electrochemical polymerization. UV-visible spectroscopy demonstrates a gradual evolution of the polaron band which indicates the electronic conductive properties of the polymers. Simultaneous possession of the water-repelling property and electron conductivity for superhydrophobic perfluorinated polyaniline leads to a unique polymer that is suitable as a solid contact in ion-selective electrodes for monitoring of pH changes during early stages of inflammation and septic shock.
View Article and Find Full Text PDFThe main task of the research is to acquire fundamental knowledge about the effect of polymer structure on the physicochemical properties of films. A novel meta-material that can be used in manufacturing sensor layers was developed as a model. At the first stage, poly(sodium 4-styrenesulfonate) () cross-linked microspheres are synthesized (which are based on strong polyelectrolytes containing sulfo groups in each monomer unit), and at the second stage, microspheres are formed.
View Article and Find Full Text PDFPolyelectrolyte microspheres find applications in many fields such as ion exchange columns, fuel cell membranes, and catalysis, to name a few. Synthesis of these microspheres by inverse emulsion polymerization offers various advantages due to the increased specific surface area and high surface charge density. The surface charge density of the obtained polyelectrolyte microspheres is a hundred times higher than that of either particles obtained by dispersion copolymerization of styrene and styrenesulfonic acid or sulfonated microspheres.
View Article and Find Full Text PDFWe show that fingerprints of the different states of water association can be clearly distinguished in the range of the first overtone of water's symmetric O-H stretching in the spectra of water-saturated [EMIm](+) -based ionic liquids with anions of substantially different hydrophilicity, such as hydrophobic [(CF3 SO2 )2 N](-) , moderately hydrophilic [CF3 SO3 ](-) , and highly hydrophilic [HSO4 ](-) .
View Article and Find Full Text PDFLiquid-crystalline state of dyes can be easy distinguished from the crystalline one by the appearance of characteristic long-wavelength optical absorption, the so-called J-band. Similarly, long-wavelength absorption of polyaniline is assumed to be the signature of its J-like liquid-crystalline state. When water evaporates from polyaniline adsorbed on a glass support during polymerization, the long-wavelength maximum at about 800 nm disappears, and one at 570 nm appears, characteristic for highly crystalline and strongly oriented thin film.
View Article and Find Full Text PDFA great number of nano/microscaled morphologies have recently been prepared during the oxidation of aniline. At the early stage of oxidation, aniline oligomers are obtained, often in spectacular morphologies depending on reaction conditions. Herein, the flower-like hierarchical architectures assembled from aniline oligomers by a template-free method are reported.
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