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Zirconia toughened alumina (ZTA) nanopowder was synthesized by solution combustion technique. Polymer nanocomposites were prepared using ZTA nanopowder as the reinforcement and polyvinyl alcohol (PVA) as the matrix. ZTA nanopowder composition was varied from 0 to 2.5% by weight. Structural characterization was done using scanning electron microscope (SEM) and X-ray diffraction (XRD). XRD results showed prominent, well defined peaks of zirconia and α-alumina, hence confirmed that ZTA is a crystalline material. SEM images showed that, level of agglomeration kept increasing due to increase in filler content, which might have contributed to film stiffness. Thermal analysis was carried out using differential scanning calorimetry. Addition of ZTA into PVA matrix resulted in increase in melting point as well as glass transition temperature. Influence of the nanofiller concentration on the electrical conductivity was found using Agilent 4249A impedance analyser. Conductivity measurements were carried out for all the nanocomposite films doped with ZTA and were found to exhibit insulating properties. Change in mechanical properties such as Young's modulus, tensile strength and film toughness of PVA films as a function of nano filler content are reported.

<abstract> <p>Epoxy composites were prepared by doping nano Zirconia Toughened Alumina (ZTA) which were synthesized by solution combustion method into epoxy resin and hardener. Initially ZTA nanopowder was characterized to check its purity, morphology and to confirm its metal-oxide bonding using XRD, SEM and FTIR respectively. The thermal properties such as TGA and DTG were also analysed. The polymer composites were obtained by uniformly dispersing ZTA nanopowder into epoxy using an ultrasonicator. Polymer composites of various concentrations viz, 0.5, 1, 1.5, 2 and 2.5 wt% were synthesized, all concentrations were prepared on weight basis. All the polymer composites were tested for compression properties, flexural properties and tensile properties. Best results for all the mechanical properties were obtained for epoxy with 1.5 wt% ZTA composites. Electrical properties such as breakdown voltage and breakdown strength were analysed and outstanding results were observed for epoxy with 2.5 wt% ZTA composite.</p> </abstract>

Cadmium oxide doped zinc oxide nanoparticles were synthesized by solution combustion technique. CdO-ZnO nanoparticles were reinforced into epoxy by ultrasonication technique. CdO-ZnO nano-particles are well known semiconducting materials which are found to exhibit excellent semiconducting behavior even at high frequencies. Hence it was introduced into epoxy to study the semiconducting nature of CdO-ZnO/epoxy composites. The polymer composites exhibited interesting phenomenon such as minimum heat losses at high frequencies indicating semi-conducting behaviour of the composites. The polymer composite was also analysed for its structural, thermal, optical and mechanical properties. The enhanced interaction of CdO-ZnO nanoparticles with epoxy has resulted in superior UV-shielding effeciency and mechanical properties. This paper mainly focusses upon the synthesis and development of CdO-ZnO/epoxy composites, the design and optimization of CdO-ZnO compositions, the mechanical toughening and failure mechanism, transport mechanism of charge carriers, conductivity relaxation, ionic polarization and prospects of CdO-ZnO/epoxy composites in various fields.

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