International Journal of Engineering Research
Year : 2013, Volume : 2, Issue : 2
First page : ( 88) Last page : ( 90)
Print ISSN : 2347-5013. Online ISSN : 2319-6890.

Thermally Stimulated Relaxation and Electrical Conduction Phenomena In Polyacrylamide

Prasad K. Rajendra

Department of Physics, Kakatiya Institute of Technology & Science, Warangal (A.P.), India. krpkits@gmail.com

Online published on 8 November, 2017.

Abstract

Thermally stimulated relaxation (TSR), employing thermally stimulated luminescence (TSL) and thermally stimulated conductivity (TSC) as experimental techniques, in Polyacrylamide (PAA) have been studied; in the temperature range 300–480 K. Measurements of electrical conductivity (σ) at various temperatures, in the same temperature range have been made, in both as-grown and UV-irradiated PAA films; to elucidate the mechanism of charge transport in relation to the macromolecular relaxations in PAA. Two TSL and TSC glow curves with maxima at 375 and 475 K have been observed. The logσ vs 1/T plots showed two transition temperatures with changes in slopes; indicating the on-set of molecular motion in PAA. The TSL/TSC curves at 475 K are attributed to the α-relaxation near the glass transition temperature of the polymer. The β-relaxation is considered to be associated with the glow curve at 375 K. Analysis of TSL/TSC curves and electrical conductivity plots have been made and the results are correlated. The two endothermic peaks recorded by Differential scanning calorimetry (DSC) are correlated with the TSL/TSC α and β-relaxations in Polyacrylamide.

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Keywords

Thermally stimulated relaxation, luminescence, Electrical conductivity, Differential Scanning Calorimetry.

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