Materiais híbridos orgânico-inorgânicos (ormosil) obtidos por sol-gel com potencial uso como filtro solar

Abstract

ORGANIC-INORGANIC HYBRID MATERIALS OBTAINED BY THE SOL-GEL METHOD WITH POTENTIAL USE AS SUNCREENS. This work aimed at the synthesis and characterization of particles of modified silica containing the organic filter dibenzoylmethane (DBM) by the hydrolytic sol-gel method, with modifications to the Stöber route. The structures of the resulting Xerogels were characterized by diffuse reflectance UV-VIS spectroscopy in the solid state, infrared absorption spectroscopy, Scanning Electron Microscopy (SEM) and 29 Si Nuclear Magnetic Resonance (29 Si NRM). The results showed favorable formation of hybrid organic-inorganic nanoparticles with efficient absorption/reflectance of radiation in the UV / VIS range, which enables their potential use as sunscreen.

Evaluation of reaction factors for deposition of silica (SiO2) nanoparticles on cellulose fibers

“…6b) shows the three main typical silica bands detectable in the regions near to 450 cm −1 , 800 cm −1 and 1100 cm −1 , which are attributed to stretching vibration of Si O Si, Si O Si and Si O C, respectively Naghsh, Sadeghi, Moheb, Chenar, & Mohagheghian, 2012). The presence of those peaks (at 450 cm −1 , 800 cm −1 and 1100 cm −1 ) strongly suggests that chemical bonding between cellulose and silica was formed after superficial modification (Ashori et al, 2012;Machado et al, 2011;Nassar et al, 2007;Shi et al, 2013).…”

Fluorescent hybrid organic–inorganic particles: influence of physical encapsulation versus covalent attachment on leaching and UV stability

“…15)21) Encapsulation of dyes reduces their release from particles into the environment and can significantly increase the dye lifetime through retardation of photochemical degradation. 22)25) These particles can be readily prepared by physical encapsulation of dyes in solid 22),26)28) or hollow silica particles (Scheme 1) 29), 30) or by copolymerization of a dye bearing monomer with a silica monomer, such as tetraethoxysilane (TEOS) (Schemes 2 and 3).…”

Organic Sunscreens. Research, Innovation and the Organic Synthesis Importance

“…109 Esta temática possui uma investigação recente, 2011 e 2012, pelo desenvolvimento de muitos e diversificados estudos. [110][111][112][113] Diversos trabalhos voltados para a síntese 93 A encapsulação polimérica é um método promissor para carrear moléculas fotoprotetoras, haja vista a grande variedade e versatilidade da química de polímeros. 7 Estes nanocompostos são frequentemente avaliados quanto a seus princípios de fotoproteção.…”