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Polymer‐in‐salt‐electrolytes (PISEs) are an important class of electrolytes as they carry the promise of faster and single ion transport. Unfortunately, due to unavailability of a suitable polymer host PISE has still not reached to commercial level. In the present work, using a novel synthesis protocol developed by the group, glutaraldehyde crosslinked wheat starch has been successfully modified with sodium iodide (NaI) to synthesize a flexible PISE membrane with desired electrochemical properties. Present paper reports the effect of crosslinker and exposure to high humidity ambience on electrochemical and morphological properties. It has been established that on exposure to higher humidity atmosphere starch‐based PISEs stabilize at lower resistance value, but with higher ion relaxation time, which indicates that effect of high humidity treatment is more on salt dissociation instead of assisting the ion transport. The studied materials have conductivity ≈0.01 S cm−1 range with ESW >2.5 V, ensuring its usability in electrochemical devices. The developed synthesis protocol does not require any complicated synthesis route and/or sophisticated instrument hence the overall process is economical also, adding up to its potentiality for energy device fabrication. [ABSTRACT FROM AUTHOR]

A conducting polymer system, having room temperature conductivity ~1.26×10−4 S/cm (for 50% NaI concentration) and ionic transference number ~0.80, has been prepared by mixing NaI in a novel polymer host (synthesized polymer+poly (ethylene oxide)). Mobility (μ) and total number of charge carriers (N), estimated from dielectric parameters, have a value of ~1.65×10−2 cm2 V−1 s−1 and 4.70×1016 cm−3 respectively. Inverse relationship between conductivity power law exponent n and N/N 0 (fractional number of dissociated charge carriers) is explained in terms of statistical nature of ion dynamics. The temperature dependence of “n” studied separately in universal power law (UPL) and super linear power law (SLPL) region revealed that exponent n responds differently to temperature in these two different regions. Ion hopping frequency (ω p), obtained from universal power law (UPL) region, is used for scaling of conductivity and permittivity curves. Conductivity scaling followed a master curve Y =1+ Xn , having n =0.85±0.07, covering both UPL as well as SLPL region which confirms that both phenomena have the same origin. [ABSTRACT FROM AUTHOR]

Abstract: A polymeric system has been synthesized using Triethylenetetramine (TETA), 1-3 Propane Sultone and Glutaraldehyde (GA) in the ratio 1:1:1. The system is doped with NaI to make it conducting. Its electrical and dielectric properties are discussed in terms of conductivity, mobility and number of charge carriers as a function of salt concentration and temperature. Maximum conductivity (~10−4 Scm−1) is obtained for 50% NaI containing system. Before melting phase transition (Tm), conductivity, number of charge carriers, mobility and diffusion coefficient are all increasing with temperature and follow Arrhenius nature but after Tm mobility follows a decreasing trend. Both in ε″ vs logω and tanδ vs logω curves peaks become sharper after melting phase transition. Distribution of relaxation time, decreases with increasing temperature and salt concentration, indicating that material has a tendency to achieve Debye type behavior. [Copyright &y& Elsevier]

A biopolymer based electrolyte system has been developed using NaI as dopant salt and Arrowroot starch as polymer matrix. Problem of fungal growth in such system has been removed by the addition of Glutaraldehyde (GA). The conductivity of the Arrowroot + NaI electrolyte system is of the order of 6.7 × 10 S cm. Starch without crosslinker GA seems to be highly unstable and prone to fungal growth whereas the GA crosslinked electrolyte is quite stable. Color of the material as well as its conductivity data indicate that presence of GA affects the salt dissociation and multiplets formation. Ionic transference number of system is ≥0.95 indicating that prepared system is ionic conductor/electrolyte. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]