Effect of Magnetite Nano Particles on p-n‐Alkyl Benzoic Acid Mesogens

Abstract

The magnetite (Fe3O4) nanoparticles (0.5 wt%) of size less than 20 nm doped inp-n-alkyl benzoic acids wherenvaries from heptyl (7) to nonyl (9) are prepared and the presence of Fe+3is confirmed through UV-Visible spectrophotometer. Textural and phase transition temperature studies are carried out using polarizing optical microscopy on pure and nano dopedp-n-alkyl benzoic acids. These results are further confirmed by DSC at a scan rate of 5ºC/min and dielectric studies. Dielectric studies are carried out, in which the variation of dielectric constant, loss and the conductivity are analyzed with respect to temperatures and frequencies. Increment of relaxation times for nano doped heptyl and nonyl benzoic acids are observed which implies that the dielectric nature is strengthened for the nano doped mesogens. The preference of nano dopedp-n-alkyl benzoic acids is discussed.

Dielectric Studies on Fe3O4Nanodopedp-n-Alkyloxybenzoic Acids

“…The phase transition temperatures for different series of those pure --alkyloxybenzoic acids [17] recorded immediately after preparation of N OBA are not similar as shown in Table 1. The clearing temperatures have decreased for nanodoped liquid crystals when compared to pure liquid crystals [18]. This decrease is due to increase in the van der Waals attraction among nanoparticles that disturbed the orientational properties of director in the LCs medium.…”