Bioactive glass-mesoporous silica coatings on Ti6Al4V through enameling and triblock-copolymer-templated sol-gel processing

AbstractPlatinum nanoparticles were dispersed in mesopores of mesoporous silica using a sol-gel process with a composite template consisting of an amphiphilic triblock copolymer (Pluronic P123 or F127) and a Pt-organic complex, which was prepared with K2Pt(II)Cl4 as a Pt source and 1,10-phenanthroline as a chelating agent. The obtained Pt-1,10-phenanthroline complex did not dissolve in any of several solvents, e.g., hexane, benzene, toluene, THF, H2O, CH3OH, and C2H5OH. However, when the Pt-1,10-phenanthroline complex was reacted with ethylenediamine it dissolved in many solvents. Platinum nanoparticles dispersed in mesoporous silica were obtained using a sol-gel process with a complex template consisting of Pt-1,10-phenanthroline-ethylenediamine, and an amphiphilic triblock copolymer (Pluronic P123 or F127). A sample dried at 353 K was bright yellow. When it was subsequently heat-treated at 823 K, it turned light gray. This change indicates that Pt nanoparticles can be obtained by heat-treatment at high temperature, because, to generate Pt nanoparticles, the organics chelated to Pt ions must be removed. Measurements from small-angle x-ray scattering show that mesoporous silica obtained using a complex template has a much more highly ordered pore structure than that obtained using only an amphiphilic triblock copolymer. It has both large pores (above 8 nm) and a large surface area (about 290 m2/g). Furthermore, results of a TEM investigation showed that Pt nanoparticles were generated only in mesopores of mesoporous silica.

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A Comparative Investigation on a Novel Bioactive Glass Synthesized via Sol-Gel Processing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.631.25 ◽

2014 ◽

Vol 631 ◽

pp. 25-29

Author(s):

S.S. Seyedmomeni ◽

M. Naeimi ◽

Majid Raz ◽

J. Aghazadeh Mohandesi ◽

F. Moztarzadeh

Keyword(s):

Bioactive Glass ◽

Sol Gel ◽

Bone Substitutes ◽

Comparative Investigation ◽

X Ray Diffraction ◽

Bioactive Glasses ◽

Bioactive Materials ◽

Proliferation And Differentiation ◽

Crystalline Domains ◽

Gel Processing

Various kinds of bioactive materials are developed as bone substitutes. Bioactive materials may affect attachment, proliferation and differentiation of cells and the subsequent integration in a host tissue. In this research 21%CaO–5%P2O5–64%SiO2–5%ZnO-5%B2O3and 16%CaO–5%P2O5–64%SiO2–5%ZnO-10%B2O3bioactive glasses were successfully synthesized by the sol–gel technique. Then the prepared bioactive glasses were soaked into simulated body fluid. Then the prepared samples were characterized using X-ray diffraction (XRD) and Scanning electron microscopy (SEM). It was seen that addition of boron to the structure remarkably enhances the formation of hydroxyapatite on the surface of the bioactive glass and subsequently improves the bioactivity. The obtained results from SEM and XRD were in good agreement with each other. Besides, effect of boron on atomic arrangement of the prepared bioactive glass was studies and compared with previous researches. It was shown that by increasing the boron content, more crystalline domains would be observed.

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Shielding of metals from the corrosion induced by water and humidity by using scratch resistant and hydrophobic silica coatings

Journal of Research in Physics ◽

10.2478/jrp-2018-0002 ◽

2018 ◽

Vol 39 (1) ◽

pp. 23-30

Author(s):

M. R. Shedam ◽

S. S. Patil ◽

Rakesh M. Shedam ◽

Shridhar N. Mathad

Keyword(s):

Corrosion Resistance ◽

Metal Surfaces ◽

Sol Gel ◽

Deposition Technique ◽

Gel Method ◽

Sol Gel Method ◽

Practical Applications ◽

Silica Coatings ◽

Hydrophobic Silica ◽

Gel Processing

Abstract The objective of the present paper is to demonstrate the effect of sol-gel derived scratch resistant coatings on different metal surfaces for anticorrosive applications. However, practical applications are limited by problems intrinsic to sol-gel processing or specific of coating/metal systems. Coatings aimed to improve oxidation and wet corrosion resistance have been studied the most. The results published in the literature show that sol-gel coatings may offer good protection against oxidation. More difficult is to achieve a protection against wet corrosion. An important aspect of the application of the sol-gel method for coating metallic objects is also the deposition technique.

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