M Tahmasebpour - ۱Nanostructure Materials Research Center (NMRC), Sahand University of Technology-Chemical Engineering Department, Sahand University of Technology
A. A. Babaluo - ۱Nanostructure Materials Research Center (NMRC), Sahand University of Technology-۲Institute of Polymeric Materials, Sahand University of Technology-۳Chemical Engineering Department, Sahand University of Technology
N. Asgari - Chemical Engineering Department, Sahand University of Technology

The aim of the present work is to synthesize nanosized α-Al2O3 and m-ZrO2 via polyacrylamide gel method and investigate the effect of initial salt and heating rate on the size of the synthesized nanopowders. Finer nanoparticles were obtained at lower heating rates as a result of delay in phase transformation s. Also, the obtained results showed that presence of nitrate or chloride ions affects the synthesized nanoparticles size via two different mechanisms: the crystallization and polymeric network degradation. Nitrate ions had an accelerator role on the degradation of polymeric network and on the other hand, retarded the crystallization and delayed the phase transformations. In zirconia synthesis, the retarded crystallization mechanism dominated over the polymeric network degradation and therefore, samples prepared by oxynitrate salt had average particle sizes smaller than that by oxychloride salts but in alumina synthesis, two entitled mechanisms eliminate the effects of each other and there is no obvious difference between particle sizes.

Polyacrylamide gel; Ceramic; Nanopowder; Heating rate; Precursor salt