Hydrophobic grade fumed silicas are generally used in tabletting as lubricants. They are also found to retard the release of pharmaceutical actives. This is because of their hydrophobic nature, which gives good cohesive and adhesive properties. considering this point it was thought that they could be used as dry COATING agents for solid dosages forms. The model drug selected for this work was paracetamol in granular form and the various COATING materials evaluated were hydrophobic grade fumed silicas such as Wacker HDK H-20, Wacker HDK H-15 and Aerosil R-972. Aerosil R-972 was found to be satisfactory and extended the release process up to 8 h at concentrations as low as 0.75%. Key parameters such as COATING, mixing duration, rotation speed in dissolution test, and medium composition were studied, which were shown not to alter the release significantly.

In this study reactive modification of polypropylene (PP) and talc composites by POWDER COATING waste (PCW) on a corotating twin screw extruder was studied and morphology and mechanical properties were evaluated. The morphological study of the composites showed that the use of POWDER COATING waste improved the dispersion of talc in PP and leads to orientation of talc plates in the flow direction of the injection mold. The PP-talc composite shows high loss of mechanical properties with thermal aging in comparison with PP-talc composites which have POWDER COATING waste (PCW). PP + Talc (20%) + PCW (20%) sample shows good resistance against to thermal aging. The improvement of thermal stability of PPTalc- PCW composites can be the result of adhering of epoxy-polyester resin of POWDER COATING waste on talc plates and also to metals impurities. The cured epoxy –polyester resin particles were played the role of stress concentrators and decreased mechanical properties such as impact strength.

Fibre content effects on mechanical, surface morphology and chemical resistance of epoxy/rattan fibre composite was investigated. By analysis of scanning electron microscopy (SEM), mechanical and chemical examinations. SEM shows the rattan fibre had improved facial adhesion and a fairly uniform distribution of fibre in the matrix. Similar result were observed for flexural and tensile strengths with gradual increase in strengths with filler loading. Mechanical properties improved with increasing fibre loading, peaking at 25 wt % content. The best tensile and impact strength was obtained at 25 wt % filler with a value of 19.271Mpa and 18.876 J/m. There was a 4.48 % increase in hardness obtained at 15 wt %, 6.55 % increase in hardness at 20 wt. %, while 7.46 % increase in hardness was obtained at 25 wt % representing the highest hardness for individual fibre wt % considered. The flexural strength obtained for the samples presented increased as fibre content increased, while the best flexural strength result of 27.542 Mpa was observed at 25 wt. % fibre. The rattan - epoxy composite’s weight reduced greatly after testing in 10% HCl, NaOCl, and NaOH solution. Theresult for immersing in H2O2 solution showed negligible effects and hence, a small reduction in weight loss.

In this study the surface of WC POWDER particles coated by Ni-P electroless process and the effect of POWDER proportion immersed in Ni-P electroless bath and the activation pretreatment on the Nickel content was evaluated by X-Ray florescence analysis. To investigate the effect of POWDER proportion immersed in electroless bath, the activated POWDER with concentrations of 20 and 40 g/lit was added in electroless bath and the weight percent of Ni assessed to be 14.1 and 7.5% respectively. To evaluate the effect of activation process, WC POWDER with concentration of 20 g/lit was immersed in Ni-P electroless bath with and without activation process. By applying the activation process, the weight percent of Ni increased about 27%. An equation was proved to estimate the thickness of electroless layer. In this approach, the thickness of electroless layer in E20, E20P andE40P samples was calculated 0.08, 1.1 and 0.05 mm respectively. In XRD pattern of Ni-P coated WC, the W2C peaks were exhibited, because of the diffusion of hydrogen in structural defects.

In this research, hydroxyapatite composite with two reinforcements alumina and zirconia has been used as a COATING on titanium dental implants for the first time. Two kinds of titanium implants with different percentages of impurities were chosen and after cleaning, they were coated with hydroxyapatite alumina-zirconia sol. The method of COATING was sol-gel that coated implants by dip-COATING and spin-COATING. The use of sol-gel method was for the reason that it is a cheap COATING method and it can coat all samples. By comparing the samples, it was found that in dip-COATING method, cracks are less and the morphology is more homogeneous. Although spin-coated samples were homogeneous too, but they had more cracks. COATING processes were done in three stages and between these stages, in second stage, COATINGs were the best in having less cracks and the best homogeneity. It was found that implants with less impurity had more homogeneous COATINGs. Increasing aging and calcination temperature of COATINGs had a great effect on the quality of COATINGs. The aim of this research was to investigate these COATINGs for COATING titanium dental implants. Because implantation is an expensive operation, we used cheap raw materials for the COATING of implants.

Nowadays, elecrochemical methods such as electrophoretic deposition are extensively used in industrial and laboratory activities, due to their high ability to control the surface morphology and the possibility for manufacturing different types of ceramic, metal and ceramic/metal composite bodies.In this research, ZrO2 electrolyte of solid oxide fuel cell is coatd on Titanium substrate. For this reason, first Zirconia POWDER was stablized in acetone and ethanol mixture by adding iodine and then electric field was applied between cathode and anode poles of cell that made the charged zirconia particles to deposit on the surface of Ti (cathode pole in cell). Effects of parameters such as solvent type, voltage, process time, zirconia POWDER and additive amounts in solvent plus sintering conditions in quality of coated layer were investigated.Results were shown that it could be possible to stabilize 20 (gI) of zirconia POWDER in two to one volumetric ratio of acetone and ethanol mixture by adding 1/2 (gI) iodine. Also applying 25 volt between the poles of cell for 20 minutes is suitable. Finally, the layer was sintered in 1250 °C temperature in hydrogen atmosphere for 2 hours.

In this study the corrosion performance of epoxy and SiAlON - epoxy nanocomposite POWDER COATINGs were investigated. Given that ball mill process has so far received little attention, in this study, nanocomposite POWDER produced by this method are discussed. Corrosion properties of COATINGs were assessed by immersion and electrochemical impedance spectroscopy tests in 3.5% NaCl solution. The results show that adding 10 wt% SiAlON nanoparticles markedly increases corrosion resistance of epoxy COATINGs. Higher corrosion resistance of nanocomposite COATINGs can be attributed to the barrier properties of SiAlON nanoparticles. According to these results, it can be concluded that epoxy POWDER COATING containing 10 wt% SiAlON nanoparticle, can be widely used as COATING pipelines in oil, gas and petrochemical industries.