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Fabrication of nanocomposite polymer-blend electrolytes comprising polyethylene oxide, polyvinyl chloride, lithium perchlorate and titanium dioxide (TiO2) (27.03 nm) has been demonstrated using the famous solvent casting technique. AC impedance measurements were carried out in the frequency range of 1 Hz–10 MHz. The effect of filler on the ionic conductivity is explained on the basis of distribution of TiO2, Lewis acid–base interaction, polymer segment-ion coupling and aggloramation of TiO2. Fourier transform infrared spectroscopy spectra showed the occurrence of complexation and interaction among the components. The crystalline and amorphous phases of the complex were identified through X-ray diffraction. Atomic force microscope pictures of the samples confirmed the plasticizing action of nano TiO2.

Terephtal-bis-p-n-decylaniline (TBDA) exhibit a weakly first order Sm A‒Sm C Phase Transition Whereas TBBA, a lower homologue of the same series, exhibit a second order Sm A‒Sm C transition. In order to investigate the tricritical point (TCP) of Sm A‒Sm C transition, a systematic study of binary mixtures of TBBA + TBDA are undertaken. DSC and polarizing thermal microscopy studies infer the TCP of the Sm A‒Sm C Transition at the weight percent of 80.05 TBDA in TBBA. We report here a systematic study of the approach of TCP by DSC and density measurements as a function of temperature in few compositions of TBBA + TBDA on both sides of the tricritical point.

We report here the study of nature of few rare phase transitions viz., Isotropic ‒ Sm C, Sm C ‒ Sm F and Srn A ‒ Sm F transition in two homologues of α, ω-bis(4-n-alkylanilinebenzylid- ine-4′-oxy)alkane series using density measurements. Compound 10.040.10 exhibits Iso- tropic ‒ Sm C, Sm C ‒ Sm F and Sm F ‒ Crystal phase transitions. Whereas 10.0100.10 exhibits Isotropic ‒ Sm A, Sm A ‒ Sm F and Sm F ‒ Crystal transitions. Variation of density with temperature across the phase transitions Isotropic ‒ Sm A, Isotropic ‒ Sm C, Sm C ‒ Sm F and Sm A ‒ Sm F show a jump in density confirming that all these transitions are first order in nature. However, the magnitude of the density jump is smaller than expected at some of these transitions. The calculated pressure dependence of transition temperature is also reported.

α,ω-bis(4-n-alkylanilinebenzylidine-4′-oxy)alkanes exhibit a rich smectic polymorphism. We have studied the variation of density as a function of temperature across the phase transitions in two compounds of the series viz., 7.O4O.7 and 7.O5O.7. Both of these compounds exhibit a rare phase transition of Sm A - Sm F. The results confirmed first order nature of the transitions of Isotropic - Sm A and Sm A - Sm F, but with a smaller jump than expected in density as compared to monomers across the transitions. The estimated pressure dependence of transition temperature is also reported. The results are discussed in the light of available literature data.