INVESTIGADORES
PROCACCINI Raul Ariel
congresos y reuniones científicas
Título:
Structure of Silver-Containing Sol-Gel Hybrid Materials and its Performance as Biocide Coatings
Autor/es:
RAÚL A. PROCACCINI; SERGIO PELLICE
Lugar:
Campinas
Reunión:
Encuentro; 23ª Reunião Anual de Usuários do LNLS; 2013
Institución organizadora:
LNLS-CNPEM
Resumen:
Development of thin biocide coatings is acquiring higher meaning since it brings
the possibility to functionalize surfaces exposed to biologic contamination and,
therefore, to inhibit the spreading of contagious infections provoked by different
microorganisms. In this work, hybrid organic-inorganic sol-gel materials were func-
tionalized with silver ions in order to analyze the relationship between the hybrid
structures, silver ion stability and biocide effect as a function of the organic component and densifying thermal treatments. Hybrid silica-methyl and silica-epoxy coatings were synthesized, through the sol-gel method, by hydrolytic condensation of tetraethoxysilane (TEOS), methyl-trimethoxysilane (MTES) and glycidoxypropyl-
trimethoxysilane (GPTMS) under acidic conditions. Silver ions were added in the
sol stage by a silver nitrate solution. Stable and colorless sols were obtained.
Through dip-coating at a constant withdrawal rate, homogeneous and cracks-free
coatings were obtained and thermally treated at 50, 100, 150 and 200 °C in air and
oxygen atmospheres. Hybrid structures and thermal evolution of silver nanoparti-
cles were analyzed by Small Angle X-ray Scattering (SAXS) at the SAXS1 beamline
of LNLS. A spinodal-like phase separation was resolved in each one of the hybrid
matrixes. Analysis of SAXS curves were compared with results from Fourier Trans-
formed Infrared Spectroscopy (FTIR), UV-visible spectroscopy and Transmission
Electron Microscopy (TEM). Biocide effect was evaluated, against Escherichia coli,
through the inhibition halo in agar diffusion tests.