Synthesis, characterization and properties of novel polyamides derived from 4 4' bis(4-carboxy methylene) biphenyl and various diamines.

Novel aromatic aliphatic diacid monomer, 4 4' bis(4-carboxy methylene) biphenyl was synthesized via friedel craft acylation with acetic anhydride followed by willgerodot reaction and used in the preparation of polyamides by direct polycondensation using the Yamazaki phosphorylation reaction with commercial aromatic diamines. These polyamides were obtained in good yield with moderate-to-high-molecular-weight build up as evidenced by inherent viscosities in the range of 0.52-0.

Synthesis and characterization of semi-aromatic polyamides containing heterocyclic 1,3,5 s-triazine and methylene spacer group for thermally stable and colloidal property.

A new aromatic diacid (II) was synthesized and Characterized by Spectroscopic techniques namely, FT-IR,  H and  C NMR, etc. A series of aromatic aliphatic polyamides containing phenoxy s-triazine ring with methylene spacer group was synthesized from diacid (II) and various aromatic diamines by using Yamazaki Phosphorylation method. These polyamides were obtained in good yields and characterized by solubility in common organic solvent, inherent viscosity, FT-IR, X-ray diffraction analysis.

Synthesis and Properties of Metal Oxide Aerogels via Ambient Pressure Drying.

Metal oxide aerogels such as zirconia (ZrO₂), titania (TiO₂), and alumina (Al₂O₃) aerogels are very interesting nanoporous materials applicable as thermal insulators, catalysts, sensors, and so on. To obtain the aerogels, the first key step is a sol-gel process to prepare the gel followed by either supercritical drying, ambient pressure drying, or freeze-drying. Although the expensive and energy-intensive supercritical drying method restricts the commercialization of the aerogels, ambient pressure drying has shown great potential as an alternative and very simple method for aerogel synthesis.

Polymethyl methacrylate (PMMA)-bismuth ferrite (BFO) nanocomposite: low loss and high dielectric constant materials with perceptible magnetic properties.

Herein, poly(methyl methacrylate)-bismuth ferrite (PMMA-BFO) nanocomposites were successfully prepared by an in situ polymerization method for the first time. Initially, the as prepared bismuth ferrite (BFO) nanoparticles were dispersed in the monomer, (methyl methacrylate) by sonication. Benzoyl peroxide was used to initiate the polymerization reaction in ethyl acetate medium.