Conducting Polymer Hybrids

Electrically conducting polymer nanocomposites (CPCs) consist of conductive nanofillers (e.g., metal nanoparticle, carbon nanotube, and graphene) and polymer matrices, which have become a greatly active field in the composite materials study. Due to their ease of processing, low density, tunable electrical properties, oxidation resistance, and flexibility, CPCs show versatile electrical applications such as antistatic protection, electromagnetic interference (EMI) shielding, energy storage electrode, sensors, flexible electronics, and thermoelectric devices. In this chapter, we review the recent progress and main challenges on CPCs and predict their development trend by several sections including the introduction, background, fabrication methods, the morphology control strategies, some application cases, and outlook. The key issues for successful fabrication of high-performance CPCs are discussed. Among them, the strategies on control of conductive network morphology and their effects on the electrical properties in CPCs are emphasized. Some interesting applications of CPCs based on the electroactive functions are described, and their property-related requirements are also proposed. We hope that the small review can provide a valuable reference for the researchers from academic and industry communities working on the CPCs and their functional devices.

This chapter reviews the state of art of nanocomposites based on conducting polymers and magnetic nanoparticles. The preparation of hybrid nanocomposites with both magnetic and electrical properties has emerging as attractive alternative in a wide number of applications especially as microwave absorbing material and electromagnetic shielding. An overview of the different synthetic routes of the hybrid nanocomposites is presented, which outlines the most development techniques to prepare homogenous matrix, core–shell nanoparticles, and thin films. This chapter also covers the discussion of both the magnetic and electrical properties of the nanocomposites that significantly vary from the individual components. Finally varies of the most relevant applications of the magnetic nanoparticles-based conducting polymer nanocomposites are highlighted.

In recent times, organic conducting polymers such as polypyrrole (PPy), polyaniline (PAni) and polythiophene (PTh) based hybrid nanocomposites have attracted the immense attention of the researchers worldwide due to their potential technological applications. Owing to their high thermal stability, redox activity, and electrical conductivity, conducting polymer nanostructures are used to entrap metal or metal oxide nanoparticles and carbon-based nanostructured materials. The hybrid nanocomposites overcome the poor processability of the metal or metal oxide nanoparticles. By combining the excellent electrical, optical and biological properties of different nanostructures with good thermal stability, biocompatibility and dielectric properties of conducting polymer nanostructures, the hybrid nanocomposites are unique multifunctional materials for varied applications in microelectronics, sensing, biotechnology, energy storage, etc. Among the conducting polymers, PPy nanostructures are gaining intensive attention due to their remarkable properties such as good environmental stability, redox activity and low toxicity and are excellent host material for metal/metal-oxide nanoparticles. Similarly, silver nanoparticles are of immense interest because of their excellent electrical, surface plasmon absorption and biocidal activity. The present chapter deals with synthesis, characterization, properties and applications of the conducting polymer nanostructures with metal/metal-oxide nanoparticles, carbon nanomaterial and ternary nanocomposites in general and polypyrrole nanotubes-silver nanoparticles hybrid nanocomposites, in particular. The different synthesis approaches of these hybrid nanomaterials with their application on the diverse field have been presented. Moreover, the chapter gives a glimpse of possible future work in this particular area. In the second part of this chapter, the dielectric, optical, antimicrobial and haemolysis activity of polypyrrole nanotubes (PPy-NTs): silver nanoparticles (Ag-NPs) hybrid nanocomposites synthesized by in situ reduction method in our laboratory will be discussed. PPy-NTs synthesized by reactive template method are used as the matrix as well as a capping agent for Ag-NPs synthesized by in situ reduction of silver nitrate. The formation of hybrid nanocomposites is revealed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The dielectric properties and ac conductivity with varying Ag-NPs loading is analyzed. Maximum conductivity of the order of 1.6 × 10⁻³ S/cm has been achieved with 15 wt% of Ag-NPs. The effect of Ag-NPs concentration on antimicrobial activity of the nanocomposites is investigated by Kirby–Bauer method. It is observed that the bactericidal performance of the nanocomposites increases with the concentration of Ag-NPs in the nanocomposites. Maximum zone of inhibition is measured around 23 mm with 15 wt% of Ag-NPs against gram negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria. The lowest minimum inhibitory concentration (MIC) values are determined as 0.078 and 0.15625 mg/ml for the nanocomposites having 15 wt% of Ag-NPs against E. coli and S. aureus, respectively. Haemolysis activity of the nanocomposites is carried out with mammalian red blood cell (RBC). All the nanocomposites exhibit haemolysis below the permissible limit of 5 % up to a concentration of 2.5 mg/mL.

In this chapter, authors have focused on various aspects of conducting polymers and their potential applications. Conducting polymers (CPs) are the very exciting class of electronic materials, which have attracted huge interest around the world since their discovery in past three decades. Conducting polymers (CPs) have several excellent reinforced properties, as compared to the non-conducting polymeric resins. In the recent years, many CPs have been used for fabrication of the electronic device, rechargeable batteries, artificial muscles, solar energy conversion, and sensors. This book chapter complies two main parts of the investigation. The first focuses most common conducting polymers. And the second is regarding their potential applications. In addition, to this authors have also added several very recent citations for further reading.

Nanomaterials have been regarded as most gifted materials for large number of scientific and technological applications. In engineering, polymer nanocomposites are a novel class of composite materials, where a clay or filler with nano size dimensions is added in a polymer matrix at a very small ratio or volume. When dispersed in contents less than 5 % in the nanocomposites, clay cause a noteworthy enhancement in various properties, such as mechanical, optical, magnetic barrier, and especially permeability and flammability resistance. In this perspective, the major goal of the present chapter is to give a brief summary about polymeric nanocomposites, their preparation and some nanocomposites based on conducting polymers. At the end, different polymeric nanocomposites obtained from the synthesis of polyaniline (PAni) with different commercial clays (Cloisite Na⁺, 10A, 15A, 20A and 30B) are described. The synthesis of PAni and montmorillonite (PAni–MMT) nanocomposites was carried out by in situ polymerization of aniline in acidic media (HCl). Electrical conductivity measurements, FT-IR, TGA and X-ray diffraction were some of the tools employed to characterize the nanocomposites. The results confirmed that it is feasible to get PAni–MMT nanocomposites by chemical synthesis method and the X-ray diffraction patterns and photomicrographs confirmed the better exfoliation of the clay by the PAni chains and the development of PAni–MMT nanocomposite.

With the advancement of electronics and mobile technologies, supercapacitors are becoming the significant energy storage device. The properties of supercapacitor depend on electrochemical properties, electrochemical stability, surface area, and electrical conductivity of advanced electrode materials. Nanohybrid materials based on conducting polymers and carbon has been substantially explored over the preceding years. Strong hybridization with carbon materials, especially with graphene has been found in effectively improving the enactment of a supercapacitor with the control of size and morphology of nanoparticles, enrichment of the electron transport by adding nanocarbons, and modification of the electronic structures through charge transfer process. We have presented an overview of supercapacitor characteristics of hybrid nanostructures with conducting polymers, and carbon materials as electrode materials and extensively discusses their future trend for practical supercapacitor applications.

The industrial demand for novel and smart materials as well as the urge for basic understanding has led to a notable improvement in the area of polymer science. Recently, significant consideration has been given to the modifications of biodegradable hydrogels based on natural polymers with conducting polymers (CPs), because this extends a straightforward process to couple the better features of CPs with the highly cross-linked hydrogels. The final hydrogels have been developed to change mainly electrical and structural properties to a larger degree. Herein, we present a comprehensive survey of the existing and current literature on conducting hydrogels based on natural polymers. This chapter also highlights ample of methods used to synthesize conducting hydrogel, properties, and characterization techniques. Conducting hydrogels have been used in the removal of dyes from wastewater, drug delivery, fuel cells, supercapacitors, dye-sensitized solar cells, rechargeable lithium batteries, etc. All these justify the rising interest in both academia and industrial development. In this analysis, an overview of potential applications of these conducting hydrogels and current challenges in the field are discussed; some new and futuristic advances in this captivating area are also provided.

Due to numerous potential applications of conducting polymers, these materials are now world wide studied since the discovery of first conducting polymer (polyacetylene) in 1977. Particularly for sensing concerned, conducting polymers are very sensitive to environmental conditions. The developments in nanostructure conducting polymers and conducting polymer nanocomposites have large impact on sensor research. Due to large surface-area-to-volume ratio of nanostructure conducting polymers, they show superior performance compared to conducting polymers in bulk form. However, the sensitivity and selectivity of nanostructure conducting polymer-based sensors still leave room for improvement. The conducting polymer nanocomposites have gained tremendous recognition in the field of sensors to improve the sensitivity and selectivity due to synergistic effect of size reduction for nanofiller and high electrical conductivity of conducting polymer in nanocomposites. Therefore, the sensitivity and selectivity of conducting polymer nanocomposites-based sensors have been enhanced compared to that of the classical materials-based sensors. This chapter provides the current research activities of the sensors/biosensors based on conducting polymer nanocomposites. The synthesis of nanostructure conducting polymers and conducting polymer nanocomposites, their application in sensors/biosensors are reviewed and discussed in this chapter.

The use of nanocomposites of electronically conducting polymers for supercapacitors has increased significantly over the past years, due to their high capacitances and abilities to withstand many charge-discharge cycles if properly structured. We have recently been investigating the use of nanocomposites of electronically conducting polymers containing conducting and nonconducting nanomaterials, such as carbon nanotubes and cellulose nanocrystals, for use in supercapacitors. In this contribution, we provide a summary of some of the key issues in this area of research. This discussion includes some history, fundamental concepts, the physical and chemical processes involved and the challenges that these nanocomposite materials must overcome in order to become technologically viable. Due to space limitations, this is not a complete review of all the work that has been done in this field and we have focussed on common themes that appear in the published work. Our aim is that this chapter will help readers to understand the advantages and challenges involved in the use of these materials in supercapacitors and to identify areas for further development.

The last decade has seen a significant interest in the composites of conducting polymers (CPs) and carbon nanotubes (CNTs). The CP–CNT composites present great interest for various applications due to the large surface area, high mechanical strength and high conductivity. The CP–CNT composites are used as actuators, fuel cells, electronic devices and ‘supercapacitors’. The topic being very vast, particular emphasis has been given to polypyrrole (PPy) and polyaniline (PANi) based CNT composites for their use as supercapacitors. Polypyrrole and polyaniline have good conductivity and are cost effective for their use in electrical applications. Both the polymers have been a key interest for supercapacitive properties in the last decade. High specific capacitance (SC), high electrochemical stability and good cyclability are the main requirements for material to be used for energy storage properties. The present chapter provides an overview of past and current research on conducting polymer/carbon nanotube (CP–CNT) composite materials for use as supercapacitor electrodes. The various factors affecting the performance, cyclic stability and charge storage properties of CP–CNT composites, such as the method used for the synthesis of the composite, shape and size of polymer nanoparticles as well as the weight percentage of both the entities in the composite have been discussed in the present chapter. An overview of current research on PPy–CNT and PANi–CNT composites for their use as supercapacitor electrodes has been given in the chapter. The focus is given towards the various factors affecting their performance with relevant literature and description.