Irradiation Effects on Structural, Microstructural and Electrochemical Properties of PEO-NH4ClO4 Polymer Electrolytes

This study investigates the effects of γ-irradiation on the structural and electrochemical properties of polymer electrolytes composed of PEO(1-x)-NH4ClO4(x) with x = 0.16, 0.20, 0.24 and 0.26. Studying the effects of different γ doses (up to 60 kGy) on the thermal transitions, microstructure, molecular weight and ion conductivity of the system is the main objective. Differential scanning calorimetry (DSC) was used to evaluate changes in crystallinity and thermal transitions, while viscosity measurements of aqueous solutions were employed to assess the molecular weight variations. The γ-irradiation caused both crosslinking and chain scission in the polymer matrix, with scission being the dominant effect. A significant increase in the ion conductivity was observed at 35 kGy, indicating improved ion transport due to enhance the amorphous character. DSC results showed a clear, exponential decrease in crystallinity with increasing dose. Viscosity data supported the occurrence of molecular weight reduction, correlating well with conductivity trends. This study provides a comprehensive analysis linking γ-induced structural modifications–particularly microstructural disorder and molecular weight changes–to enhanced ion transport in PEO-NH4ClO4 polymer electrolytes. The observed exponential decline in crystallinity with dose reinforces the mechanism of γ-induced crosslinking and scission.