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Drying of alkyd emulsion paints / P. K. Weissenborn in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 906 (07/2000)
[article]
Titre : Drying of alkyd emulsion paints Type de document : texte imprimé Auteurs : P. K. Weissenborn, Auteur ; A. Motiejauskaite, Auteur Année de publication : 2000 Article en page(s) : p. 65-74 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Agents dispersants (chimie)
Cobalt
Dioxyde de titane
Pigments inorganiques
Polyalkydes
Revêtements -- Additifs
Revêtements en phase aqueuse:Peinture en phase aqueuse
SiccatifsUn siccatif est une substance qui joue un rôle de catalyseur en accélérant le séchage ou durcissement (polymérisation) d'un matériau tel une huile ou une peinture à base d'huile (pour le bâtiment ou les artistes).Tags : 'Matériau revêtement' 'Peinture eau' émulsion' 'Alkyde résine' 'Formation film' Séchage Siccatif 'Cobalt Composé' 'Pigment minéral' 'Titane Oxyde' Adjuvant Dispersant 'Etude expérimentale' Index. décimale : 667.9 Revêtements et enduits Résumé : The drying and film formation of long oil alkyd emulsions was investigated with emphasis on loss of dry upon storage. The main reason for loss of dry was adsorption of the cobalt (drier) on pigment surfaces as a precipitated hydroxide. Titanium dioxides with alumina surface treatment and organic pigments were most detrimental to drying. Acrylate- and phosphate-based dispersants also deactivated the cobalt, presumably due to complexation and precipitation of the cobalt. Emulsions prepared with an emulsifiable cobalt drier containing 2,2'-bipyridyl (complexing agent for cobalt) showed the best resistance to loss of dry. Atomic force microscopy of films formed from the emulsions showed that the emulsifier migrated to the film surface which, when washed with water, leaves holes or pits in the film. The pits were arranged in a hexagonal pattern characteristic of Bénard cells, which form due to surface tension and/or temperature gradients generated in the film during evaporation of water. Note de contenu : - MATERIALS: Alkyd resins - Emulsifiers - Driers - Dispersants - Pigments - Other Reagents
- METHODS: Alkyd resin emulsification - Addition of dispersants to LO83 alkyd emulsions - Addition of pigments to LO83 Alkyd emulsions - Storage stability and loss of dry tests - BK drying tests - Emulsion characterization - Film formation studies
- DRYING PROPERTIES OF PURE ALKYD EMULSIONS: Effect of emulsion pH - Effect of cobalt form and location - Other variables
- DRYING PROPERTIES OF EMULSIONS CONTAINING PIGMENT DISPERSANTS
- DRYING PROPERTIES OF EMULSIONS CONTAINING PIGMENTS
- FILM FORMATIONPermalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17987
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 72, N° 906 (07/2000) . - p. 65-74[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 001211 - Périodique Bibliothèque principale Documentaires Disponible Biosynthesis of a UV stable pigment : prodigiosin / V. Natarajan in PAINTINDIA, Vol. XLV, N° 10 (10/1995)
[article]
Titre : Biosynthesis of a UV stable pigment : prodigiosin Type de document : texte imprimé Auteurs : V. Natarajan, Auteur ; P. K. Kamath, Auteur Année de publication : 1995 Article en page(s) : p. 23-33 Note générale : Glossaire - Bibliogr. Langues : Anglais (eng) Tags : Biosynthèse Pigment Prodigiosine 'Serratia marcescens' 'Culture de microorganismes' Mutagenèse Optimisation 'Zinc II Ion' Mutation 'Cobalt 'Milieu culture' 'Nickel 'Elément trace' 'Fer Nutriment 'Titane 'Irradiation UV' 'Molybdène Enterobacteriaceae Bactérie Index. décimale : 667.9 Revêtements et enduits Résumé : Pigment Prodigiosin is red maroon in colour and has a pyrrye dipyrryl methene structure. It is water insoluble and occurs membrane bound in the cells of Serratia marcescens, which is gram negative bacterium. As the parent strain of Serratia marcescens NRRL B284 was found to be unstable in its pigment synthesising ability, an attempt was therefore made to derive UV stable mutants employing UV induced mutagenesis. Out of seven mutants derived, a lone mutant designed M2 was found to be most promising both in terms of stable pigment producing characters as well as faster growth rates in select synthetic medium compared to the rest of the mutants. Studies on mutant M2 constitue optimisation of Carbon:Nitrogen ratio in the synthetic medium selected, followed by studies on feeding salts of trace cations during cell cultivation (as nutrient modifiers) to explore further (if any), scope for improving the UV stability of the pigment synthesised. The role/contribution towards UV stability by trace cations e.g. Mo++, Ti++, Fe++, Ni++, Co++ and Zn++ were investigated. Select UV stable pigments were evaluated for their performance in two types of air drying paints, with intersting results with respect to colour and gloss retention Note de contenu : HISTORY OF PROIDOGIOSIN
- SCOPE OF CURRENT WORK
- MATERIAL AND METHODS
- EXPERIMENTAL : Culture maintenance and inoculum preparation - Screening of media for pigment production - Optimisation of carbone : nitrogen ratio for pigment synthesis - Cell harvesting, determination of biomass, pigment extraction - Chromatographic analysis of pigment - Reversion to chromogenic variants - Role of oxygen - Straint improvement through UV mutagenesis - Screening of salts of trace cations as nutrient modifiers - Pigment screening for uv stability - Prodigiosin for paint application
- RESULTS AND DISCUSSION : Reversion to chromogenic variants - UV induced mutagenesis and effect of mutation - Effect of oxyten - Effect of optimising carbon : nitrogen in synthetic medium for mutant M2 - Composition of MSM - Effect of trace cations on UV stability of pigment - Performance of prodigiosin in paints - IR interpretationPermalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=13665
in PAINTINDIA > Vol. XLV, N° 10 (10/1995) . - p. 23-33[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 006457 - Périodique Bibliothèque principale Documentaires Disponible