Poly styrene -Based Electrolytes

Compared with PEO electrolytes, PDVF, and PMMA electrolytes exhibited higher ionic conductivities. In particular, PMMA has attracted increasing attentions due to its low cost, high solvent retention ability, high transparency, and processibility. The first allpolymer electrochromic device was obtained based on a gel electrolyte and PEDOT-PSS [poly(styrene sulfonate)] electrochromic material (Argun et al., 2003). The fabricated device exhibited a maximum transmittance change of 51% at 540 nm. In addition, this device was fairly stable and only 5% contrast loss was observed after 32,000 cycles. 

Sellam, and S. A. Hashmi. 2013. High rate performance of flexible pseudocapacitors fabricated using ionic-liquid-based proton conducting polymer electrolyte with poly(3, 4-ethylenedioxythiophene) poly(styrene sulfonate) and its hydrous ruthenium oxide composite electrodes. ACS Applied Materials Interfaces 5 3875-3883. 

Over the last decade, several new proton exchange membranes have been developed. The new polymers in fuel cell applications are based mostly on hydrocarbon structures for the polymer backbone. Poly(styrene sulfonic acid) is a basic material in this field. In practice, poly(styrene sulfonic acid) and the analogous polymers such as phenol sulfonic acid resin and poly(trifluorostyrene sulfonic acid), were frequently used as polymer electrolytes for PEMFCs in the 1960s. Chemically and thermally stable aromatic polymers such as poly(styrene) [ 3 ], poly(oxy-1,4-phenyleneoxy-1,4-phenylenecarbony 1-1,4-phenylene) (PEEK) [4], poly(phenylenesulfide) [5], poly(l,4-phenylene) [6, 7], poly (oxy-1,4-phe-nylene) [8], and other aromatic polymers [9-11], can be employed as the polymer backbone for proton conducting polymers. These chemical structures are illustrated in Fig. 6.2. 

Very early hydrocarbon-based membranes tested as electrolytes in PEMECs for Gemini space missions, such as sulfonated phenol-formaldehyde resins, sulfonated poly(styrene-divinylbenzene) copolymers, and grafted polystyrene sulfonic acid membranes, were chemically weak, and therefore PEMFCs using these membranes showed poor performance and had only lifetimes of several hundred hours (LaConti et al. 2003). Nafion , a PESA membrane, was developed in the mid-1960s by DuPont (LaConti et al. 2003). It is based on an aliphatic perfluorocarbon sulfonic acid, and exhibited excellent physical properties and oxidative stability in both wet and dry states. A PEMEC stack using Nafion 120 (250- tm thickness, equivalent weight = 1,200) achieved continuous operation for 60,000 h at 43-82°C (LaConti et al. 2003, 2006). A Nafion -based PEMFC was used for the NASA 30-day Biosatellite space mission (LaConti et al. 2003). 

Akhtar et al. [902(a)] were one of the first to describe completely assembled, sealed, solid-state electrochromic devices based on CPs. In one set of devices, the fairly common Li-triflate/Poly(ethylene oxide) (PEO)/acetonitrile formulation for nonaqueous solid electrolytes was used. However, in another set, the unique combination of poly(ethyleneimines) of different MWt and protonic acids such as hydrochloric, sulfuric, phosphoric, acetic and poly(styrene sulfonic) was used. Additionally, the films of the CP, P(ANi), were prepared electrochemically as well as by sublimation, and in one set of devices Fe-tungstate was used as a counter electrode to provide a definitive counter electrode reaction (Lithiation). While cyclabilities to several thousand cycles were claimed, the electrochromic dynamic range and other parameters were fairly poor, as seen in Figs. 20-3. Very rapid switching times have been claimed for many P(ANi)- or P(ANi)-derivative based devices. For example. Ram et al. [902(b)] claimed a 143 ms switching time for liquid-electrolyte devices based on poly(aniline-co-o-anisidine). 

Polyelectrolyte multilayers (PEMs) are very important materials due to having a wide range of application helds such as encapsulation of drugs and enzymes, membrane-based separations, antibacterial coatings, membrane reactors and fuel cells. Polyelectrolyte multilayer (PEM) has a wide range of transport properties, simple deposition and small thickness, so it can be used in separation membranes. Polyelectrolyte concentration, duration and temperature of adsorption, deposition and solution pH are key parameters for specific separations. In addition the number of poly electrolyte layers can alter the properties of poly electrolyte. Poly (styrene sulfonate) (PSS)/poly(diallyldimethylammonium chloride) (PDADMAC) films are utilized in separation membranes. The adsorption of Cu(II) or Fe(III) ions can be carried out with PSS/poly(allylamine hydrochloride) (PAH) membranes. 

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