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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.

Corrosion inhibitors for copper immersed in emulsion were investigated by experiments and theoretical calculations, and this study aims to propose a new inhibition mechanism of the inhibitors having protective effects for copper corrosion.

Adsorption behavior of penta-heterocycles (thiophene, 1,2,5-oxadiazole, furan, 2 H-1,2,3-triazole, pyrrole and 1,2,5-thiadiazole) as corrosion inhibitors for copper immersed in oil-in-water (O/W) emulsions was investigated by weight loss, electrochemical tests, morphological characterization and theoretical calculations.

The orders of inhibition effect are furan < pyrrole < thiophene < 1,2,5-oxadiazole < 2H-1,2,3-triazole < 1,2,5-thiadiazole, and 1,2,5-thiadiazole at 0.5 mM has the best inhibition effect for copper immersed in emulsion. The results of scanning probe microscope, scanning electron microscope and electrochemical test show that a protective barrier can be formed on the surface of copper substrate with six corrosion inhibitors, thus effectively inhibiting the corrosion of copper mainly through chemisorption and following Langmuir’s adsorption isotherm.

Quantum chemical and molecular dynamic simulations demonstrate that all these compounds attached to Cu matrix with a flat-adsorption mode to prevent the emulsion corrode copper. Adsorbed inhibitors act as a barrier at Cu matrix to block corrosion and improve hydrophobicity.

The purpose of this paper is to synthesise the block copolymer of pyrrole (Py) with bis(4‐inobutyl)polydimethylsiloxane (DA.PDMS) by electrochemical method. The characterisation of the insoluble block copolymers, P(Py‐b‐DA.PDMS), was performed by cyclovoltammetric measurements, solid‐state conductivity and DSC measurements. The surface morphology of the copolymers was examined with scanning electron microscope (SEM).

Electropolymerisation process was performed potentiostatically and potentiodynamically. Redox behaviour of the resulting copolymer films was investigated. In‐situ spectroelectrochemical measurement was carried out on indium thin oxide (ITO) electrodes.

The ionisation potentials (Ip), electron affinity (Ea), optical band gap (Eg), peak potentials (Ep), and doping degree (y) of copolymers were calculated by using in‐situ spectroelectrochemical measurement results. The copolymers have slightly lower doping degree, band gap, Ip and Ea values than homopolymer. Copolymers had the conductivities of 10‐5 S/cm and had Tg values.

This study can also be focused on obtaining conductive copolymer with insulator DA.PDMS blocks on the PPy chain by one‐step polymerisation.

This work provides technical information for the synthesis and characterisation of conducting block copolymer by electrochemical method.

Change in optical and electrical properties of the P(Py‐b‐DA.PDMS) shows the role of the individual properties of the copolymer blocks. While the DSC scan of PPy showed no transition temperature, which is a characteristic property of conducting copolymers, P(Py‐b‐DA.PDMS) had Tg values. This might be due to the inclusion of the DA.PDMS blocks on the PPy chains.

The purpose of this study is to explore the synthesis of novel conductive photo-resins to produce flexible conducting composites for use in additive manufacturing. By using direct ink writing (DIW) additive manufacturing, this study aims to explore the fabrication of multimaterial devices with conductive and insulating components. Using digital light processing (DLP) additive manufacturing, this study aims to fabricate detailed objects with higher resolution than material extrusion 3D printing systems.

In this paper, several photocurable conducting resins were prepared for DIW and DLP additive manufacturing. These resins were then cured using 405 nm near UV light to create intrinsically conductive polymer (ICP) composites. The electrochemical properties of these composites were analysed, and the effect of co-monomer choice and crosslinking density was determined. These results determined a suitable resin for subsequent additive manufacture using DIW and DLP. These 3D printing techniques were used to develop flexible conducting devices of submillimetre resolution that were fabricated with unmodified, commercially available 3D printers.

Cyclic voltammetry and volume conductivity analysis of the conducting resins determined the most conductive resin formula for 3D printing. Conductive devices were fabricated using the two 3D printing techniques. A multimaterial soft conducting device was fabricated using DIW, and each conducting component was insulated from its neighbours. DLP was used to fabricate a soft conducting device with good XY resolution with a minimum feature size of 0.2 mm. All devices were prepared in unmodified commercially available 3D printers.

These findings have value in the development of soft robotics, artificial muscles and wearable sensors. In addition, this work highlights techniques for DIW and DLP additive manufacturing.

Several original conducting resin formulae were developed for use in two 3D printing systems. The resulting 3D-printed composites are soft and flexible while maintaining their conductive properties. These findings are of value to both polymer chemists and to the field of additive manufacturing.

The purpose of this study is to investigate the effect of the spacer length of zinc porphyrin-TiO₂ hybrids by photodegradation of methyl orange (MO) in aqueous solution under visible light.

5-Mono-[4-hydroxyphenyl]-10,15,20-triphenylporphyrin was synthesized using Alder method. A new series of porphyrins and their corresponding zinc complexes (ZnPp) were obtained from 5-mono-[4-hydroxyphenyl]-10,15,20-triphenylporphyrin via nucleophilic substitution reaction. The ZnPp-TiO₂ photocatalysts were prepared by loading ZnPp onto TiO₂ and characterized by scanning electron microscope, X-ray diffraction, UV-vis diffuse reflectance spectrum and X-ray photoelectron spectroscopy.

The results indicated that zinc porphyrins were successfully loaded on the surface of TiO₂ microsphere, which is crucial to enhance the activity of the catalytic composite under visible light. All the novel photocatalysts showed much enhanced photoactivity than bare TiO₂. Among all the prepared ZnPp-TiO₂, 5,10,15-triphenyl-20-[4-(4-naphthoxy)-butoxy]phenyl zinc porphyrin-TiO₂ (4b) showed the highest photocatalytic activity for the degradation of MO.

Synthesis of these zinc porphyrins had never been reported previously.

Four novel zinc porphyrin-TiO₂ photocatalysts which could response to visible light in degradation of MO were synthesized using Alder method. The results show that the photocatalytic activity of 5,10,15-triphenyl-20-[4-(4-naphthoxy)butoxy] phenyl zinc porphyrin- TiO₂ is higher than others.

This paper aims to synthesise block copolymers (PPy-b-ENP) of pyrrole (Py) and ethoxylated nonyl phenols (ENP) via redox systems in presence of ceric ammonium nitrate (CAN) at room temperature. The initiating radical was formed on reducing organic compound which in turn initiated polymerisation to give diblock copolymers containing chain ends of ENPs and polypyrrole (Ppy). The effects of the concentration of Ce⁺⁴ salt, ENPs and Py on both the yield and electrical conductivities of corresponding polymers were studied.

In total, 0.1 M stock solution of CAN:100 ml 1 M HNO₃ was prepared freshly (7 ml HNO₃ dissolved in 100 ml water) and used in 50 ml of 0.1 M CAN solution (2.7438 g CAN dissolved in 50 ml nitric acid solution). The reducing compound (Py) was dissolved in water. Py and ENP were added slowly to the flask with vigorous stirring. The content of the flask was flushed with oxygen-free nitrogen. The resulting copolymers were characterised with spectroscopic methods like Fourier transform infrared spectroscopy and scanning electron microscope.

In this study, DMSO-slightly soluble Py copolymers were produced with ENPs. The conductivities of copolymers were found to be in the range of 10-1 to 10-4 S/cm. Soluble and processable conductive polymers were developed.

In this study, the water solubility of ENPs diminishes the conductivity of copolymer because of its surfactant structure. When the CAN/Py ratio was increased, PPys and copolymers with both higher yield and lower conductivity values were obtained. The results indicated that solubilities and the yield of the polymers synthesised in the presence of ENP have increased considerably. ENP caused degradative chain transfer reaction to become significant compared with bimolecular termination, so the yield decreased with increasing ENP concentration about 20 g/l. Results showed that yield of the copolymers strongly depends on Ce⁺⁴ concentrations while of copolymers were measured to be 10-3 S/cm.

PPy-b-ENP diblock copolymers were prepared with Ce⁺⁴ as an oxidation agent in a single step.

These slightly soluble and conductive copolymers may overcome difficulties in the applications of PPy homopolymers and open new application areas.

PPy-b-ENPs of lightly soluble (in DMSO) and conductive (10-2 S/cm) copolymers have been synthesised in one step. The results indicate that the surface of the copolymer is composed of well-distributed nanospheres with an average particle diameter of 35-400 nm.

The purpose of this paper is to investigate microwave reflection, transmission, and complex permittivity of p‐toluene‐2‐sulfonic acid doped conducting polypyrrole coated nylon‐lycra textiles in the 1‐18 GHz frequency with a view to potential applications in the interaction of electromagnetic radiation with such coated fabrics.

The chemical polymerization of pyrrole is achieved by an oxidant, ferric chloride and doped with p‐toluene sulfonic acid (pTSA) to enhance the conductivity and improve stability. Permittivity of the conducting textile substrates is performed using a free space transmission method accompanied by a mathematical diffraction reduction method.

The real part of permittivity increases with polymerization time and dopant concentration, reaching a plateau at certain dopant concentration and polymerization time. The imaginary part of permittivity shows a frequency dependent change throughout the test range. All the samples have higher values of absorption than reflection. The total electromagnetic shielding effectiveness exceeds 80 percent for the highly pTSA doped samples coated for 3 h.

A non‐contact, non‐destructive free space method thin flexible specimens to be tested with high accuracy across large frequency range. The non‐destructive nature of the experiments enables investigation of the stability of the microwave transmission, reflection, absorption and complex permittivity values. Moreover, mathematical removal of the diffraction enables higher accuracy.

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.

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.

This study aims to fabricate a multifunctional electromagnetic interference (EMI) shielding composite fabric with simultaneous high-efficiency photothermal conversion and Joule heating performances.

A multifunctional polypyrrole (PPy) hydrogel/multiwalled carbon nanotube (MWCNT)/cotton EMI shielding composite fabric (hereafter denoted as PHMC) was prepared by loading MWCNT onto tannin-treated cotton fabric, followed by in situ crosslinking-polymerization to synthesize three-dimensional (3D) conductive networked PPy hydrogel on the surface of MWCNT-coated cotton fabric.

Benefiting from the unique interconnected 3D networked conductive structure of PPy hydrogel, the obtained PHMC exhibited a high EMI-shielding effectiveness vale of 48 dB (the absorbing electromagnetic wave accounted for 84%) within a large frequency range (8.2–12.4 GHz). Moreover, the temperature of the laminated fabric reached 54°C within 900 s under 15 V, and it required more than 100 s to return to room temperature (28.7°C). When the light intensity was adjusted to 150 mW/cm², the PHMC temperature was about 38.2°C after lighting for 900 s, indicating high-efficiency electro-photothermal effect function.

This paper provides a novel strategy for designing a type of multifunctional EMI shielding composite fabric with great promise for wearable smart garments, EMI shielding and personal heating applications.