Inclusión de plata y cobre en sílice sol-gel para su uso como aditivo antimicrobiano

Existe un gran interés en el desarrollo de nuevos materiales con alto valor agregado, tales como materiales biodegradables, inteligentes, o que incorporan el uso de nanotecnología para mejorar alguna de sus propiedades.Centro de Investigación y Desarrollo en Ciencias Aplicada

Inclusión de plata y cobre en sílice sol-gel para su uso como aditivo antimicrobiano

Existe un gran interés en el desarrollo de nuevos materiales con alto valor agregado, tales como materiales biodegradables, inteligentes, o que incorporan el uso de nanotecnología para mejorar alguna de sus propiedades.Centro de Investigación y Desarrollo en Ciencias Aplicada

Inclusión de plata y cobre en sílice sol-gel para su uso como aditivo antimicrobiano

Existe un gran interés en el desarrollo de nuevos materiales con alto valor agregado, tales como materiales biodegradables, inteligentes, o que incorporan el uso de nanotecnología para mejorar alguna de sus propiedades.Centro de Investigación y Desarrollo en Ciencias Aplicada

Chemoselective preparation of 1,1-diacetates from aldehydes, mediated by a Keggin heteropolyacid under solvent free conditions at room temperature

A simple, general and efficient method has been developed for the conversion of aldehydes to 1,1-diacetates using acetic anhydride, a catalytic amount of non commercial Keggin heteropolyacid (H6 PalMo11O40) (1% mol) in solvent free conditions at room temperature. Aromatic and aliphatic, simple and conjugated aldehydes were protected with excellent yields.Facultad de Ciencias Exacta

Assessment of waterborne coatings formulated with sol-gel/Ag related to fungal growth resistance

Fungal growth in damp surfaces of water-damaged buildings is an increasing problem around the world, which has adverse effects on both people's health and buildings. By bio-deterioration, fungi can growth in indoor environments and generate materials losses in addition to health problems. Therefore, antifungal coatings must be developed to avoid these problems. Silica is used as supporting additive in coatings, such as the waterborne paints and, on the other hand, the addition of Ag nanoparticles into different materials is being widely studied for its effective antimicrobial properties. The aim of this work was to evaluate the bio-resistance to fungal growth on waterborne coatings containing siliceous additives, by accelerated four-week agar plate assay. The additives were synthesized by the sol-gel method and characterized by potentiometric titration and transmission electron microscopy (TEM). In addition, the paints were observed by scanning electron microscopy (SEM) at the end of the test. To carry out the bioresistance assay, Chaetomium globosum and Alternaria alternata fungi were used. After 4 weeks of assay, paints prepared with the silver-additives were the most efficient inhibiting the growth of both fungi. These paints, after their exposure for 6 months, in an internal environment with sunlight incidence, kept the antifungal activity against Chaetomium globosum and showed a higher activity against Alternaria alternata.Centro de Investigación y Desarrollo en Ciencias Aplicadas (CINDECA)Centro de Investigación y Desarrollo en Tecnología de Pinturas (CIDEPINT

Chemoselective preparation of 1,1-diacetates from aldehydes, mediated by a Keggin heteropolyacid under solvent free conditions at room temperature

A simple, general and efficient method has been developed for the conversion of aldehydes to 1,1-diacetates using acetic anhydride, a catalytic amount of non commercial Keggin heteropolyacid (H6 PalMo11O40) (1% mol) in solvent free conditions at room temperature. Aromatic and aliphatic, simple and conjugated aldehydes were protected with excellent yields.Facultad de Ciencias Exacta

Prevención microbiológica usando síntesis de nuevos materiales funcionalizados con heteropolioxometalatos via química verde

Uno de los desafíos ambientales en la actualidad es el control microbiológico en ambientes cerrados. Por lo tanto, es de vital importancia contribuir en la prevención y/o limitación de la proliferación microbiológica, en especial, en ambientes cerrados. En tal sentido es fundamental la evaluación de nuevos agentes antimicrobianos que puedan ser aplicados en diversas áreas de desarrollo de materiales de construcción y de recubrimientos protectores. Los esfuerzos globales de reducir desechos peligrosos y los procesos limpios se están integrando tanto en ciencia como en la industria.En esta investigación se trabajará con residuos de semillas de girasol funcionalizadas con 3-aminopropiltrietoxisilano, como soporte de aditivos, a los que se les agregará un compuesto de Mo y K, que actuará como antimicrobiano, en pinturas higiénicas. El sólido proveniente de las semillas de girasol será funcionalizado mediante reacciones entre organosilanos y los grupos superficiales del sólido mencionado. La caracterización de los sólidos se realizará mediante SEM-EDS, DRX, FT-IR, propiedades texturales, titulación potenciométrica, entre otras.Estos sólidos fueron evaluados microbiológicamente frente a hongos y bacterias de interés, dando resultados promisorios para los noveles aditivos ecológicos para ser utilizados en una siguiente etapa en la formulación de pinturas higiénicas.At the present time one of the environmental challenges is the microbiological control in the indoor environment. Therefore, it is of vital importance contribute to avoid and/or minimize the microbiological growth in the indoor environments. In such sense the evaluation of new antimicrobial agents is fundamental and can be applied in diverse areas of development of protective coating and construction materials. The global efforts to reduce to dangerous remainders and technologically clean are being integrated as in science as in the industry. In this investigation will work with remainders of seeds of sunflower functionalized with 3-aminopropyltriethoxysilane, as support of additives, to a compound of Mo and K, that will act as antimicrobial, to be used in hygienic paintings. The originating solid of the sunflower seeds will be functionalized by means of reactions between organosilanes and the superficial groups of the mentioned solid. The characterization of synthesized solids will be made by means of SEM-EDS, DRX, FT-IR, textural properties, potentiometric titration, among others. These solids were microbiologically evaluated in front of fungi and bacteria, having given promissory results for novels ecological additives in hygienic paintsResumen de tesis - Departamento de Química, Facultad de Ciencias Exactas, UNLP.Facultad de Ciencias Exacta

Prevención microbiológica usando síntesis de nuevos materiales funcionalizados con heteropolioxometalatos via química verde

Uno de los desafíos ambientales en la actualidad es el control microbiológico en ambientes cerrados. Por lo tanto, es de vital importancia contribuir en la prevención y/o limitación de la proliferación microbiológica, en especial, en ambientes cerrados. En tal sentido es fundamental la evaluación de nuevos agentes antimicrobianos que puedan ser aplicados en diversas áreas de desarrollo de materiales de construcción y de recubrimientos protectores. Los esfuerzos globales de reducir desechos peligrosos y los procesos limpios se están integrando tanto en ciencia como en la industria.En esta investigación se trabajará con residuos de semillas de girasol funcionalizadas con 3-aminopropiltrietoxisilano, como soporte de aditivos, a los que se les agregará un compuesto de Mo y K, que actuará como antimicrobiano, en pinturas higiénicas. El sólido proveniente de las semillas de girasol será funcionalizado mediante reacciones entre organosilanos y los grupos superficiales del sólido mencionado. La caracterización de los sólidos se realizará mediante SEM-EDS, DRX, FT-IR, propiedades texturales, titulación potenciométrica, entre otras.Estos sólidos fueron evaluados microbiológicamente frente a hongos y bacterias de interés, dando resultados promisorios para los noveles aditivos ecológicos para ser utilizados en una siguiente etapa en la formulación de pinturas higiénicas.At the present time one of the environmental challenges is the microbiological control in the indoor environment. Therefore, it is of vital importance contribute to avoid and/or minimize the microbiological growth in the indoor environments. In such sense the evaluation of new antimicrobial agents is fundamental and can be applied in diverse areas of development of protective coating and construction materials. The global efforts to reduce to dangerous remainders and technologically clean are being integrated as in science as in the industry. In this investigation will work with remainders of seeds of sunflower functionalized with 3-aminopropyltriethoxysilane, as support of additives, to a compound of Mo and K, that will act as antimicrobial, to be used in hygienic paintings. The originating solid of the sunflower seeds will be functionalized by means of reactions between organosilanes and the superficial groups of the mentioned solid. The characterization of synthesized solids will be made by means of SEM-EDS, DRX, FT-IR, textural properties, potentiometric titration, among others. These solids were microbiologically evaluated in front of fungi and bacteria, having given promissory results for novels ecological additives in hygienic paintsResumen de tesis - Departamento de Química, Facultad de Ciencias Exactas, UNLP.Facultad de Ciencias Exacta

Green chemistry in Brazil

The philosophy of green chemistry has been very well received in Latin America's research and development programs. In this review we describe the green chemistry contributions of Brazilian research groups over the last three years.Centro de Investigación y Desarrollo en Ciencias Aplicada

Valorization of citrus waste: use in catalysis for the oxidation of sulfides

The utilization and valorization of industrial waste is an effective strategy for environmental protection. Since the juice industry generates a huge amount of citrus waste, we studied the application of thermally treated orange peel in catalysis. On the other hand, Keggin heteropolyacids are excellent oxidant catalysts used as a replacement for conventional oxidants; however, their solubility in polar solvents and the low specific area limit their use as heterogeneous catalysts. The utilization of treated orange peel as heteropolyacid support for the selective oxidation of sulfides is presented here. Firstly, orange peel was thermally treated, and then it was incorporated with heteropolyacids (PMo) during the silica synthesis by the sol-gel method. Therefore, SiO2-PMo, SiO2-OP100-PMo, and SiO2-OP200-PMo were obtained, characterized by FTIR, SBET, XRD, and potentiometric titration, and were tested as heterogeneous catalysts in the selective oxidation of sulfide to sulfoxide in a greener process: H2O2 as oxidant and ethanol as solvent, at 25 °C.Centro de Investigación y Desarrollo en Ciencias Aplicada