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Future Perspectives of Polymer Supercapacitors for Advanced Energy Storage Applications
Published in Soney C George, Sam John, Sreelakshmi Rajeevan, Polymer Nanocomposites in Supercapacitors, 2023
Ajalesh Balachandran Nair, Shasiya Panikkaveettil Shamsudeen, Minu Joys, Neethumol Varghese
PANi is one of the mainly auspicious dynamic materials appropriate for pseudocapacitor electrode applications. PANi, which can be synthesized by polymerization of aniline monomer and exhibit a wide variety of benefits such as ease of processing and preparation, ingenuous chemistry of doping and de-doping of acid-base, and ecological firmness [27]. The surface morphology of PANi exhibit an immense effect on their electrical and chemical properties. So, the adoption of a suitable and high-productivity synthesis method is vital for synthesizing PANi using an appropriate nanostructure. PANi developed as nanofibers in an aqueous medium in chemical oxidative polymerization, [28] and a wide variety of polymerization techniques were designed to procure PANi nanofibers [29–31]. One of the conventional, simple, and comparatively less expensive methods is interfacial polymerization. Sivakumar et al. [32] studied and reported the electrochemical properties of PANi nanofibers synthesized by means of interfacial polymerization. Though the cyclic stability of supercapacitors was very poor, a high specific capacitance of 554.0 F/g at a current of 1.00 A/g was sensed. Li et al. [33] reviewed hypothetical and experimental capacitances of PANi in acidic medium. The theoretical value of capacitance was evaluated to be 2000 F/g which was greater than experimental value. Conductance of PANi and diffusion of counter ions establish a great contribution towards the capacitance. Even a little amount of PANi influences the specific capacitance.
Nanoparticles Based Composites and Hybrids Functionalities and Synthetic Methods and Study Cases
Published in Esteban A. Franceschini, Nanostructured Multifunctional Materials Synthesis, Characterization, Applications and Computational Simulation, 2021
Victoria Benavente Llorente, Antonella Loiácono, Esteban A. Franceschini
As an alternative method, in situ interfacial polymerization has also been used for the preparation of nanomaterials-based PMC. Zhu et al. (2018) used interfacial polymerization to prepare sulphur covered carbon nanofibres embedded in a PANi matrix, as a high-performance cathode for Li-S batteries. Interfacial polymerization involves the contact of two immiscible phases, containing an initiator and monomer separately. On contact of the two immiscible phases, the initiator will start the polymerization in the interface, suppressing secondary growth and allowing it to obtain nanofibres.
Preparation Techniques
Published in Mihir Kumar Purkait, Randeep Singh, Membrane Technology in Separation Science, 2018
Mihir Kumar Purkait, Randeep Singh
Interfacial polymerization is a method involving the deposition of a polymer thin layer over a microporous support to prepare an anisotropic membrane, as shown in Figure 3.7. This method was first developed by John Cadotte at North Star Research. He used the polymer polyethylenimine and chemical toluene-2,4-diisocyanate [1]. Mulder [2] and Baker [3] explained the preparation method as the deposition of a reactive prepolymer, for example, polyamine, in the pores of a microporous membrane support, usually a polysulfone ultrafiltration membrane. This amine-containing membrane support is then immersed in a water-immiscible solvent bath containing a reactant, like diacid chloride. The reaction between the amine and acid chloride takes place at the interface of the two immiscible solutions, which results in a very thin membrane layer over the membrane support. The thin layer of membranes prepared by this method is very dense and highly cross-linked. The very low thickness of the polymer layer gives high permeability, and high cross-linking imparts high selectivity to the prepared membranes. The membrane layer has to be finely porous to withstand the extreme pressures applied but at the same time must have high porosity to have good permeability. The interfacial polymerization method is easy to follow at the laboratory scale but difficult to take to an industrial or large scale, due to the complexities involved in the development of equipment for the production of the membranes. The interfacial polymerization method is widely used for the production of reverse osmosis membranes. The membranes prepared by this method are not used for gas separation because the membrane layer consists of a hydrogel, which when dry forms a glassy polymer. This glassy polymer in turn fills the membrane support pores and block the membrane, though the selectivity of such membranes are high but have reduced permeabilities for gases.
A review on surface modification methods of poly(arylsulfone) membranes for biomedical applications
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Vahid Hoseinpour, Laya Noori, Saba Mahmoodpour, Zahra Shariatinia
Surface coating is a technique in which a thin layer is immediately deposited as a thin film coating layer that adheres non-covalently to the top surface of membrane [1,29]. Coating techniques can be classified into five approaches: (1) coating possibly followed by curing with heat, (2) coating of a hydrophilic thin layer by physical adsorption, (3) deposition from a glow discharge plasma, (4) coating with a monolayer employing analogous or Langmuir–Blodgett techniques, and (5) extrusion or casting of a two-polymer mixture by simultaneous spinning employing e.g. a triple orifice spinneret. In the final approach, using distinct solvents for every polymer mixture simplifies adhesion between the coating material and the polymeric membrane [1]. Always, a chemical reaction is not happened in surface coating modification technique. For interfacial polymerization, the polymerization reaction happens at/near the interface of two incompatible mixtures. Generally, the reaction occurs when a water-soluble monomer and a monomer soluble in an organic solvent get together at the interface of water and an organic solvent that is immiscible in water. Through employing interfacial polymerization technique, polymers could be coated onto poly(arylsulfone) membranes, and the polymerization happens at the surface and pores of the membrane. Nevertheless, the improved PES membranes are invariably flat-sheet membranes; thus, it is hard to improve hollow fiber membranes by this technique [29]. The surface coating is an efficient and simple approach for modification of the poly(arylsulfone) membranes although it is not enough stable. However, the electrostatic interactions between positively charged membrane and negatively charged coating agent enhance the stability of the membrane. It is essential to mention that the hemocompatibility of coating agents is usually relevant with their groups that are negatively charged such as the carboxylic acid and sulfonic acid groups. The anticoagulant and bioactivity of coating agents would be reduced after coating via their electrostatic interactions [7].