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The copolymer ethylene oxide and epichloridrine doped with lithium perchlorate shows interesting properties as an ionic conducting polymer mainly because of its amorphous structure at room temperature and its low glass transition temperature (T g = − 40 °C). 13C, 7Li, and 1H nuclear magnetic resonance studies were performed in order to analyze the interactions between the polymer matrix and the dopant salt with solvent molecules. These studies and conductivity measurements were used to investigate the influence of the preparation method and the properties of the solvent on the physicochemical characteristics of the polymer electrolyte. Experimental results show that solvent molecules are retained in the solid polymer electrolyte, strongly modifying its ion transport dynamic. This fact can be related to the increase in the ionic conductivity when solvent molecules rest inside the polymer matrix, producing a plasticizing effect.

In order Lo acquire new informntion about the normal-incommensurate (IC) phase transition and to check the existence of a lock-in transition in 4,4'-dichlombiphenyl sulphone (4.4'-0Css), a comprehensive "Cl nuclear quadrupole resonance (NQR) study is reported.Detailed NOR mwurements of frequency, line width and spin relaxation time ( T I ) were obtained in the temperature range 80-270 K. The results show that the IC phose is present from 1.50 K down to 80 K. The behaviour of the NQR spectrum in the trmsition region suggests that the IC modulation IS dominated by the first-order term in the order panmeter. The tt values at the p e L s of the IC specmm are quite different, suggesting strong onharmonic effects. No lock-in rrmsition was detected at 115 K. Small changer in the temperature behaviour of the frequency and the tl of the low-frequency IC peak were observed from temperatures lower than 110 K. Neither impurities nor thermal hysteresis effects were detected.