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Study on required energy to deagglomerate pigmentary titanium dioxide in water / R. T. Abrahao in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 11, N° 2 (03/2014)
[article]
Titre : Study on required energy to deagglomerate pigmentary titanium dioxide in water Type de document : texte imprimé Auteurs : R. T. Abrahao, Auteur ; V. Postal, Auteur ; J. L. Paiva, Auteur ; R. Guardani, Auteur Année de publication : 2014 Article en page(s) : p. 239-253 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Dioxyde de titane
Dispersions et suspensions
Pigments métalliques
Revêtements:PeintureIndex. décimale : 667.9 Revêtements et enduits Résumé : The dispersion process is used in various industries, including coatings, paper manufacturing, and food processing. All of these industries base their developments and technology of particle dispersion on theories that consider spherical particles in simple systems. The objective of this study was to improve understanding of the impact of these theories when applied to nonspherical/nonideal particles. Effective dispersion allows for a reduction in the use of the powder to achieve the specified final properties. This paper reports experimental results on the required energy (RE) used to disperse five different titanium dioxide (TiO2) samples into liquids with different values of surface tension [deionized (DI) water and DI water containing surfactants]. The selection of the TiO2 samples was based on different particle sizes with the same surface properties, and similar sizes with different surface properties. The results showed that the particle shape is fundamental in determining the RE for dispersion, once it defines the number of interactions among the particles. The larger the number of interactions, the more energy is required to deagglomerate the particles. An empirical equation was developed to describe the energy required for pigment dispersion as a function of the ratio between the liquid and the particle surface tensions and the particle shape factor. DOI : 10.1007/s11998-013-9534-y En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-013-9534-y.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=21168
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 11, N° 2 (03/2014) . - p. 239-253[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 16196 - Périodique Bibliothèque principale Documentaires Disponible Use of optical density and TiO2 light scattering / R. T. Abrahao in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 206, N° 4624 (09/2016)
[article]
Titre : Use of optical density and TiO2 light scattering Type de document : texte imprimé Auteurs : R. T. Abrahao, Auteur ; R. Umemura, Auteur ; Michael P. Diebold, Auteur Année de publication : 2016 Article en page(s) : p. 33-36 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Dioxyde de titane
Dispersions et suspensions
Lumière -- Absorption
Lumière -- Diffusion
Revêtements en bâtiment:Peinture en bâtiment
Revêtements:PeintureIndex. décimale : 667.9 Revêtements et enduits Résumé : Optical density is a technique to evaluate light scattered by particles suspended in a liquid paint. The authors discusses how to identify optimisation potential in architectural coatings.
Optical density (OD) is a technique for evaluating the amount of light scattered by particles suspended in a liquid paint. Using an improved OD procedure, it is now possible to quantify titanium dioxide (TiO2) light scattering efficiency in a paint without knowing the complete paint formulation. This information can be coupled with conventional spread rate measurements, which measure the scattering coefficient of the TiO2 in the dry film, allowing the paint formulator to determine the likely benefit of improving initial TiO2 dispersion or improving dispersion stability in an under performing paint.
In addition, application of the improved OD test and the conventional spread rate procedure to South and Latin American commercial paints revealed how well the TiO2 particles were dispersed in the liquid paint and how evenly they were distributed in the dry paint film - parameters termed the TiO2 dispersion efficiency and the formulation efficiency, respectively. A wide range of efficiencies was seen in the commercial paints, with almost 20% of the paints demonstrating an opportunity to benefit from improved TiO2 dispersion efficiency, while 55% showed an opportunity to improve formulation efficiency.Note de contenu : - TiO2 dispersion in dry film
- Optical density
- Spread rate
- Application to commercial paintsEn ligne : https://drive.google.com/file/d/1FJTiJU_bezN76NEs74yJ56ZX2Pu2nb-s/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=27743
in POLYMERS PAINT COLOUR JOURNAL - PPCJ > Vol. 206, N° 4624 (09/2016) . - p. 33-36[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 18317 - Périodique Bibliothèque principale Documentaires Disponible Wettability study for pigmentary titanium dioxide / R. T. Abrahao in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 10, N° 6 (11/2013)
[article]
Titre : Wettability study for pigmentary titanium dioxide Type de document : texte imprimé Auteurs : R. T. Abrahao, Auteur ; V. Postal, Auteur ; J. L. Paiva, Auteur ; R. Guardani, Auteur Année de publication : 2013 Article en page(s) : p. 829-840 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Dispersions et suspensions
Mouillabilité
Mouillage (chimie des surfaces)
Pigments inorganiques
PoudresIndex. décimale : 667.2 Colorants et pigments Résumé : Wetting is the first step in the dispersion process of any powder. Understanding how the powder surface and the liquid properties affect the speed and intensity of the wetting process provides a set of tools to determine the dispersion efficiency as a whole, and an effective dispersion allows the reduced use of the powder to achieve the specified final properties. This article reports experimental results on the wetting behavior of five different TiO2 samples by liquids with different values of surface tension [deionized (DI) water and DI water containing surfactants] and its effect on the dispersion process. The selection of the TiO2 samples was based on different particles sizes with similar surface properties, and similar sizes with different surface properties. The samples were characterized in terms of their specific surface area and particle size distribution. The wetting behavior was evaluated by a capillary rise technique (Washburn) to measure liquid penetration height and rate, and the time evolution of the particle size distribution. The results show that larger particles presented faster wettability and that liquids with lower surface tension facilitate the wetting of the powder. The energy required to deagglomerate the powder is inversely proportional to the wetting speed: the faster the wetting the easier it will be to disperse the particles, with less energy required. DOI : 10.1007/s11998-013-9530-2 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-013-9530-2.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=19822
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 10, N° 6 (11/2013) . - p. 829-840[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15744 - Périodique Bibliothèque principale Documentaires Disponible