Preparation Of Nano Research Articles

Preparation of Nano sized TiO2/Pt/Glass Thin Films by Sol-gel Method and Their Use in Photoelectric Degradation of Soluble Dye

Preparation of Nano sized TiO2/Pt/Glass Thin Films by Sol-gel Method and Their Use in Photoelectric Degradation of Soluble Dye

Preparation of Nano sized TiO2/Pt/Glass Thin Films by Sol-gel Method and Their Use in Photoelectric Degradation of Soluble Dye

Preparation of Nano sized TiO2/Pt/Glass Thin Films by Sol-gel Method and Their Use in Photoelectric Degradation of Soluble Dye

Preparation of nano- and microspheres by polycondensation techniques.

Particle-forming polycondensation techniques can be divided into two main categories, namely normal polycondensation and interfacial polycondensation. Various normal polycondensation procedures employed for the preparation of nano- and microspheres are covered by this review, and are described under suspension polycondensation, dispersion polycondensation and precipitation polycondensation. Among these, suspension polycondensation procedures are generally applicable for the preparation of both nano- and microspheres. They are employed for the production of industrially important polycondensates such as phenolics, polyesters and polyurethanes, as well as for novel polymeric materials such as polycyclodextrins, mercury-binding polymercaptals, and polyurea microcapsules. Dispersion polycondensation leads to the formation of monodisperse nanoparticles, but it is not widely employed. Precipitation polycondensation produces non-spherical and polydisperse particles, and it is useful only if low molecular weights of the polymer and polydispersity of the particles do not adversely affect the intended application of the product.

Preparation of polymer nano- and microspheres by vinyl polymerization techniques.

The methodologies and techniques of producing polymer particles (nano- and microspheres) from vinyl monomers are described, with an emphasis on laboratory preparations. Five different techniques are employed in the preparation of polymer micro- and nanoparticles from vinyl monomers. Emulsion polymerization provides particles of about 50-200 nm in diameter, emulsifier free emulsion polymerization produces particles of about 100-1000 nm (0.1-1.0 micron), dispersion polymerization gives particles in the region of 0.3-10 micron, and suspension polymerization leads to the formation of particles of about 20 micron-2 mm. The gap in the 10-20 micron region may be filled by either seeded polymerization or by more elaborately performed suspension polymerization. All of the four techniques mentioned above produce regular, spherical particles. Precipitation polymerization, on the other hand, gives irregularly shaped particles in the range of 0.1-10 micron. An attempt is made to clarify the underlying differences between these techniques and to say how they are practised in the laboratory.