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The purpose of this paper is to present fabrication process of volatile organic compounds (VOCs) sensors based on polypyrrole material deposited on different substrates and to show and compare the responses of the produced sensors to different VOCs.

Polypyrrole sensing layers were prepared by in situ chemical polymerisation on two different substrates: alumina and poly(ethylene terephthalate) (PET). The time of the polymerisation was varied. After film deposition, an interdigitated electrode was screen-printed on the material deposited on the substrate.

It was demonstrated that both polymerisation time and substrate type provide means to vary the sensitivity of polypyrrole-based sensors to VOCs.

VOCs, which are released in manufacturing or use of various products and materials, pose a threat to the environment and human health. Therefore, measures must be taken to control their concentration both in indoor and outdoor air.

Deposition of a conductive polymer film on the substrate via in situ chemical polymerisation followed by screen-printing of an interdigitated electrode on the polymer surface offers a fast and an effective method of chemiresistor-type sensor fabrication.

The paper aims to discuss the evaluation of anti-corrosive efficiency of conducting polymer, polypyrrole in water borne epoxy-polyamine coatings.

Polypyrrole (PPy) is synthesised by chemical oxidative polymerisation. The synthesised PPy is characterised by employing FT-IR, XRD, SEM and EDX analysis. The coatings are formulated using water borne epoxy cross-linked with aliphatic polyamine adduct and the effect of PPy on corrosion prevention is studied. PPy was used as anti-corrosive pigment in concentration varying from 1 to 5 wt.%. In addition to anti-corrosive property; mechanical properties, chemical resistance and weathering properties of the coatings containing PPy are studied, thereby obtaining a wholesome data about the quality and performance of these coatings.

The result obtained through various tests showed that the coating with 1 and 2% PPy exhibited excellent weathering resistance, mechanical properties and improved chemical resistance. Higher percentage loading of PPy (beyond 3 per cent) proves to be disastrous, as extended percolation networks are formed which results in rapid intense corrosion leading to fast coating breakdown.

The anti-corrosion property of the coating can be tested by means of atmospheric exposure such as Florida test which produces a real time evaluation of the anti-corrosive nature of the coating at natural condition rather than accelerated weathering, thereby providing more reliable performance data for intended application purpose.

The results find application in anti-corrosive/performance paints for industrial application.

This research paper presents the results of anti-corrosion behaviour of PPy in water borne epoxy-polyamide coating. Based on this result, a highly effective anti-corrosive coating can be formulated by the addition of small percentage of PPy in combination with other conventional pigments, thereby enhancing corrosion protection. But care must be taken so as to avoid formation of extended percolation network of PPy which leads to rapid coating breakdown.

Although conducting polymers have various potential applications, lack of solubility is an impediment in their direct application to material surfaces. Synthesis of alkyl pyrrole monomers and subsequent polymerization into soluble conducting polymers are aimed as alternatives to conventional methods of application of conducting polymers on substrates. Alkyl chains are attached to a pyrrole ring to produce solubility in the resulting conducting polypyrroles, which allow direct application of conductive polymer emulsions to any desired surface. Friedel-Crafts acylation of the tosyl-protected pyrrole provides high yields of the 3-acylated product. The conductivity values of poly-3- and 3, 4-substituted pyrroles are generally less than the unmodified polypyrrole. Increasingly bulkier groups attached to the pyrrole means lower conductivity of the resultant polymer. As the carbon chain length attached to the 3-position of pyrrole increases, the solubility also increases. However, the magnitude of change in conductivity of films and pellets of soluble conducting polypyrroles over the alkyl range is not significant.

The purpose of this paper is to review the challenges present in the development of hand exoskeletons powered by pneumatic artificial muscles. This paper also presents the development of a novel strain sensor and its application in a five‐fingered hand exoskeleton.

The issues of current hand exoskeletons powered by pneumatic artificial muscles are examined by studying the artificial muscles and the human hand anatomy. Traditional sensors are no longer suitable for applications in hand exoskeletons. A novel strain sensor was developed by depositing a conducting polymer called polypyrrole onto a natural rubber substrate through vapor phase polymerization and is used in the authors' five‐fingered hand exoskeleton.

The error of measurements from the polypyrrole strain sensor in controlling the actuation of pneumatic artificial muscles is within 1.5 mm. The small physical size and weight of the novel polypyrrole strain sensor also helped to keep the exoskeleton's profile (less than 20 mm) and total weight low (<1 kg).

The novel strain sensor allows the realization of hand exoskeletons that are lightweight, portable and low profile. This improves the comfort and practicality of hand exoskeletons to allow their usage outside the research environment.

The purpose of this paper is to synthesize polypyrrole/SiO₂ composite coating on 316 stainless steel (316SS) by cyclic voltammogram and preliminary do research about the valuable effects of SiO₂ particle incorporation within the polymer matrix.

This study is based on elaboration of coating by electrochemical process and of SiO₂ by a sol-gel process.

Electrochemical impedance studies revealed that compared with polypyrrole (PPy), PPy-SiO₂ coating acts as a more protective layer on 316SS against corrosion in 3.5 per cent NaCl. Scanning electron microscopy studies revealed that the PPy-SiO₂-coated 316SS showed more uniform and compact morphology.

To fully disperse SiO₂, a sol-gel method is used. Hydroxyl group is generated on the surface of inorganic particle by the sol-gel method, which improves the inorganic particle dispersion.

Soluble conducting alkyl polypyrrole polymers have been applied by either chemical polymerization of the 3-alkyl monomers or direct application of polymer emulsion to the surface. Solution, vapor and spray polymerization methods of coating poly(3-alkylpyrroles) to the surface of woven wool fabrics are explored. Conductive textile samples have also been prepared by applying emulsions of soluble prepolymerized 3-alkylpyrrole to the fabric surface. Direct applications of a conductive paint to the textile surface eliminate the exposure of the substrate to damaging oxidizing agents which allow the coating of more sensitive and delicate substrates. All textiles produced are tested for abrasion resistance and conductivity. For alkyl polypyrrole coated fabrics, the optimum carbon chain lengths are between n=10 and n=14, which result in optimum values of conductivity and solubility. The darkness of the tone is inversely related to the surface resistivity of the resulting conductive fabric. Therefore, deep black coatings have low resistivity whereas light gray coatings on a white fabric surface have higher surface resistivity. Longer alkyl chains result in higher surface resistivity in fabrics. The conductive coating of poly(3-decanylpyrrole) on the textile surface has a better abrasion resistance compared to that of an unsubstituted polypyrrole coating.

The aim of this paper is to conduct a real time evaluation of polypyrrole as an anti‐corrosive pigment in epoxy polyamide coating.

This study deals with synthesis of polypyrrole (PPy) by chemical oxidative polymerisation in laboratory conditions. The synthesised PPy was characterised by employing FT‐IR, XRD, SEM and EDX analysis. Epoxy film of bisphenol type hardened with polyamide based curing agent was used as the binder. PPy was used as anti‐corrosive pigment in concentrations varying from 0 to 5 wt% in the coating. In addition to anti‐corrosive property, mechanical, chemical and weathering properties of the coating containing PPy were studied and compared with epoxy polyamide coating without PPy.

The result obtained through various tests showed that the coating with 1 and 2% PPy exhibited excellent weathering resistance, mechanical properties and improved chemical resistance.

The anti‐corrosion property of the coating can be tested by means of atmospheric exposure such as Florida test or by means of electrochemical impedance spectroscopy.

The results find application in anti‐corrosive paints for industrial application.

This research paper presents the results of anti‐corrosion behaviour of PPy in epoxy‐polyamide coating. Based on this result, a highly effective anti‐corrosive coating can be formulated by addition of small percentage of PPy in combination with other conventional pigments, thereby enhancing corrosion protection.

This study examines the resistance change in conductive polypyrrole-coated PET fabrics under the AS 2001.4.15 – 1994 laundering test conditions. The effects of individual detergent components of a standard detergent, including auxiliary chemicals, at four different temperatures were studied. When the coated fabric was washed under the AS 2001.4.15-1994 conditions, the ECE reference detergent and pure soap flakes (sodium sterate) both decreased the conductivity of the coating at a rate exponentially proportional to the laundering temperature. Detergent types had an influence over the rate of degradation; pH conditions had a large influence on the rate of polymer deterioration with the acidic nonionic detergent giving rise to significantly improved laundering conditions. The auxiliary chemicals, sodium carbonate and sodium perborate were seen to cause large degradation of polymers during laundering. Ethylene diamine tetra acetic acid was seen to have only a slight influence on the reduction of conductivity of polymers.

Polypyrrole (PPy)-coated fabric can be produced by means of chemical vapour deposition using pyrrole in the presence of an oxidizing agent. This electrically conductive fabric can be used as a strain sensor, and has high potential for producing wearable sensors that can detect the movements of the wearer. Since direct contact between this conductive fabric and human body will be involved, an investigation of the effect of different types of liquids such as sweat, rain water, drinking water, etc. on the electrical conductivity of fabric sensors is critical. Changes in the conductivity and surface morphology of the PPy-coated textile were analysed by placing few drops of liquid onto the fabrics. The results showed that the electrical resistance of the PPy-coated fabrics was different when the fabrics came into contact with different types of liquid. The phenomenon can be explained by both the fibre/fibre contact and yarn/yarn contact models as well as by the uniformity of the PPy-coating layer on the surface of the fibre.

Polypyrrole (PPy) and PPy/metal oxide nanocomposites were synthesized by oxidative polymerization process, and its corrosion protection ability was studied by immersion test and electrochemical corrosion studies in 1 per cent HCl and 3.5 per cent NaCl solution.

The prepared composites were loaded in acrylic resin and subsequently coated on a mild steel surface. The characterization of the polymer composites using FT-IR, UV-vis, XRD and FE-SEM with EDS analysis confirmed the interaction between PPy and metal oxide nanoparticles. The PPy nanoparticles were less protected on the mild steel, but the nanocomposite coating with metal oxide nanoparticles dramatically increased the corrosion resistance.

According to the corrosion protection ability of the coating, it was demonstrated that the acrylic resin coating composed of PPy/metal oxide nanocomposites was highly efficient in protecting the mild steel compared to the PPy nanoparticles. The highest protection efficiency was obtained by PPy/TiO2 nanocomposites with acrylic resin coating.

To the best of the authors’ knowledge, this paper consists of original, unpublished work which is not under consideration for publication elsewhere and that all the co-authors have approved the contents of this manuscript and submission.