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In this work, we have investigated and compared three important parameters: resistance, absorbance, and sensitivity of the sensitive layer in the ammonia gas sensor made of conductive polymers. Using a simulation based on the Langmuir absorption model, we have examined the changes in resistance, absorbance, and sensitivity of both the pure conducting polymer and the layer doped with carbon nanotubes. We analyzed the results using Matlab software. The findings demonstrate that the addition of carbon nanotubes reduces the resistance and enhances the absorbance and sensitivity.

The paper deals with the effect of two conductive polymers (polyaniline, PANI, and polypyrrole, PPy) in combination with inorganic particles on the response of silicone-oil suspensions. Conductive polymers cause a significant increase in electrorheological response. PANI combined with silica is much more efficient when in the form of a thin layer on the particle surface than if the two components are simply mixed. All combinations are followed from the viewpoint of viscosity and yield stress.

This paper reports on some physical properties of a conducting polymer, polypyrrole, coated textiles. Polypyrrole was coated on textiles chemically through in-situ solution or vapor polymerisation to produce conducting textiles. The effects of the conductive coating on the physical and mechanical properties of the fibrous materials are presented. The coating durability and conductivity of the textiles have also been examined.

We present a simple method for enhancing the bandwidth and absorptivity of metamaterial perfect absorber (MPA)-formed disk resonators. Utilizing low-conductivity polymer and near-field coupling of multi-band resonances, a 6.8 GHz broadband MPA is achieved with absorption over 90%. The proposed MPA also shows polarization-independent absorption behavior. Furthermore, the structural design is useful for making broadband MPA and can be applied to higher frequencies with a simple configuration.

Zinc oxide nanoparticles in the form of particles and rods were synthesized using the hydrothermal method. The scanning electron microscopy (SEM) examination was performed. The results of the SEM tests showed the nanoscale size of zinc oxide nanoparticles was (75 nm) for particles and (150 nm) for rods. An X-ray diffraction examination was carried out, and a comparison was made between the diffraction pattern of the ZnO nanoparticle and the rods. The results showed that the ZnO nanoparticle is in the hexagonal wurtzite phase of the structure of the particles and rods. Zinc oxide nanoparticles (particles and rods) produced by the hydrothermal method have been used as an additive in polyvinyl alcohol (PVA) polymer matrix to form PVA–ZnO NPs composite thin films. The optical properties of the membrane were studied using ultraviolet–visible examination, which showed a decrease in the energy gap of the composite thin film compared to the pure membrane. While the electrical properties of composite thin film, including resistivity, mobility and majority carrier charge carriers of composite thin film, were measured using the Hall effect measurement. The results showed that zinc oxide nanoparticles have a higher conductivity than nanorods.

The structural and energetic properties of polyfluorene and its derivatives were investigated, using quantum chemical calculations. Conformational analysis of bifluorene was performed by using ab initio (HF/6-31G* and MP2/6-31G*) and density functional theory (B3LYP/6-31G*) calculations. The results showed that the local energy minimum of bifluorene lies between the coplanar and perpendicular conformation, and the B3LYP/6-31G* calculations led to the overestimation of the stability of the planar pi systems. The HOMO-LUMO energy differences of fluorene oligomers and its derivatives — 9,9-dihexylfluorene (DHPF), 9,9-dioctylfluorene (PFO), and bis(2-ethylhexyl)fluorene (BEHPF) — were calculated at the B3LYP/6-31G* level. Energy gaps and effective conjugation lengths of the corresponding polymers were obtained by extrapolating HOMO-LUMO energy differences and the lowest excitation energies to infinite chain length. The lowest excitation energies and the maximum absorption wavelength of polyfluorene were also performed, employing the time-dependent density functional theory (TDDFT) and ZINDO methods. The extrapolations, based on TDDFT and ZINDO calculations, agree well with experimental results. These theoretical methods can be useful for the design of new polymeric structures with a reducing energy gap.

Conducting polymer, polyaniline (PANI), has been studied as a novel electroactive and electrically conductive material for tissue engineering applications. The biocompatibility of the conductive polymer can be improved by (i) covalently grafting various adhesive peptides onto the surface of prefabricated conducting polymer films or into the polymer structures during the synthesis, (ii) co-electrospinning or blending with natural proteins to form conducting nanofibers or films, and (iii) preparing conducting polymers using biopolymers, such as collagen, as templates. In this paper, we mainly describe and review the approaches of covalently attaching oligopeptides to PANI and electrospinning PANI-gelatin blend nanofibers. The employment of such modified conducting polymers as substrates for enhanced cell attachment, proliferation and differentiation has been investigated with neuronal PC-12 cells and H9c2 cardiac myoblasts. For the electrospun PANI-gelatin fibers, depending on the concentrations of PANI, H9c2 cells initially displayed different morphologies on the fibrous substrates, but after one week all cultures reached confluence of similar densities and morphologies. Furthermore, we observed, that conductive PANI, when maintained in an aqueous physiologic environment, retained a significant level of electrical conductivity for at least 100 h, even though this conductivity was decreasing over time. Preliminary data show that the application of micro-current stimulates the differentiation of PC-12 cells. All the results demonstrate the potential for using PANI as an electroactive polymer in the culture of excitable cells and open the possibility of using this material as an electroactive scaffold for cardiac and/or neuronal tissue engineering applications that require biocompatibility of conductive polymers.

The electrochromic properties of an electrochemical polymerized composite consisted of polyaniline doped with acid red dye (PANI-ARD) are reported. The structures of PANIARD were characterized via cycle voltammograms, spectroelectrochemistry and colorimetric analysis. Film of the PANI-ARD composites of different concentrations appears violet, aubergine in the neutral state and darkblue in the oxidized state, which are different from the pure PANI of yellow (-0.8V) and blue (1.0V). The oxidation and reduction response speed of PANI-ARD was a bit lower than those obtained in pure PANI. It is shown that acid dye doping is an effective method to broaden the color change range of the electrochromicmateials.