Search

Polymer-based materials are of high potential for application as active materials in contemporary electronic gadgets. The functionality of such materials is highly dependent on their oxidation state and requires fine control during their synthesis. Owing to that, we have designed a cost-effective, simple, portable, system for calibration and the detection of the optical and electrical properties of polyaniline loaded on a paper substrate using a smartphone-based colorimetric sensor. The vapor phase polymerization technique was adopted for preparing polyaniline. Colorimetric measurements of polyaniline-loaded papers were achieved by estimating the hue, saturation and value (HSV) color parameter values using an open-source smartphone application called 'Color Grab (Color Detection)' during synthesis at different time intervals. The proposed sensor relies on the principle of Beer-Lambert law. The rear camera of the smartphone acts as a sensor and captures the light signal from the samples and provides information to the colorimetric app. The colorimetric results showed a promising correlation between the color parameter values with their electrical properties. The optical absorbance results of all polyaniline-loaded papers are also in accordance with the H parameter values. The proposed sensor can be used as a portable smartphone-based point-of-care testing kit to bring in-situ control during synthesis. Highlights * Conducting polymer on flexible cellulose substrate. * Smartphone-based visual colorimetric sensor. * Biodegradable and environment-friendly electronic material. * Variation of electrical properties in terms of hue values. * Cheap, portable sensor for point-of-care testing. KEYWORDS charge transport, colorimetry, conducting polymer, point-of-care testing, portable, smartphone application, 1 | INTRODUCTION The evolution of polymers is now an emerging topic in the field of materials and nanoscience. Different polymer materials are evolving for application in electronic and optoelectronic [...]

Tuning of hole transport and optical properties were accomplished in polyaniline incorporated flexible paper during vapor phase polymerization process. Vapor phase polymerization of aniline using FeCI3 as polymerizing agent was done in a reaction chamber, where the concentration of Fe[Cl.sub.3] on paper played the key role in tuning its properties. The energy band gap and electrical conductivity of the polyaniline incorporated paper have been tuned effectively during the polymerization process. The band gap changes from 2.45 eV to 2.65 eV, when the electrical sheet resistance varied from 1.0 x [10.sup.5] [OMEGA]/[] to 4.33 x [10.sup.7] [OMEGA]/[] in response to the different FeCI3 concentration. The electrical sheet resistance can be tuned within a range of two order of its value. Polymer-based electronic materials with outstanding electrical conductivity due to their delocalized molecular orbitals are of great interest in the recent development of materials chemistry and physics. Paper being a flexible substrate and incorporated with a hole transporting medium like polyaniline in its emeraldine base form will find its significant role in designing flexible electronic devices. POLYM. ENG. SCI., 58:2249-2255, 2018., INTRODUCTIONThe conductive polymers are appearing in the central focus of solid state physics because of their outstanding charge transport properties. Exploration and stimulation of the charge transport properties by employing [...]

Research has been conducted on N-cinnamoyl-L-proline. The use of this compound as a template for the synthesis of tripeptide derivatives which are the structural analogues of HIV protease inhibitors is described.

Finely tuned phosphoramidite ligands are used for preparing either the [C.sub.20] (R)- or (S)-derivatives without mutual contamination. A new highly stereoselective, ligand-dependent protocol is described for the installation of exocyclic stereocenters in a steroid D-ring through asymmetric hydrovinylation.

A highly efficient halide- or alkoxide-free yttrium complex has catalyzed the ring opening of epoxides that are mediated by TMSCN and TMS[N.sub.3]. Substrate to catalyst ratios up to 1000 are obtained from the reactions, which is run under solvent-free conditions.

Byline: Biswajit. Saha Conventionally, DNA based investigations for fetal diseases are done by chorionic villous sampling and amniocentesis. Both are invasive techniques. Recently, molecular diagnosis has also been made possible [...]