Dépouillements

Microstructure of weathered paint and its relation to gloss loss : computer simulation and modeling / Fern Y. Hunt in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 880 (05/1998)

[article]  inJOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 70, N° 880 (05/1998) . - p. 45-54 Titre : Microstructure of weathered paint and its relation to gloss loss : computer simulation and modeling Type de document : texte imprimé Auteurs : Fern Y. Hunt, Auteur ; Michael A. Galler, Auteur ; Jonathan W. Martin, Auteur Année de publication : 1998 Article en page(s) : p. 45-54 Note générale : Bibliogr. Langues : Américain (ame) Tags : Peinture  Vieillissement  'Dégradation  photochimique'  Feuil  'Propriété  optique'  Brillant  Microstructure  'Simulation  numérique'  Modélisation  Pigment  'Dimension  particule'  'Concentration  pigmentaire  volumique'  Dispersion  Formulation Index. décimale : 667.9 Revêtements et enduits Résumé : The role of pigment particle size, pigment volume concentration, and dispersion in gloss loss of paint films on weathered surfaces is unclear. Because reproducible and cost effective data are difficult to obtain, an approach based on computer simulation and modeling is a promising supplementary tool. We describe the simulation of a painted surface consisting of pigment particles of known size, pigment volume concentration and dispersion, situated in a binder that erodes over time due to exposure to ultraviolet radiation. Pigment particle size, geometry, pigment volume concentration, and pigment particle dispersion are parameters of the model. Our purpose is to illustrate how simulation can be used to aid the development of formulation strategies for the design of coatings with desirable gloss characteristics. Note de contenu : - Description of simulation - Modeling and analysis of gloss in photodegraded surfaces - Results of simulation Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17994 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
003549	-	Périodique	Bibliothèque principale	Documentaires	Disponible

A new approach in the development and testing of antifouling paints without organotin derivatives / K. Vallee-Rehel in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 880 (05/1998)

[article]  inJOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 70, N° 880 (05/1998) . - p. 55-63 Titre : A new approach in the development and testing of antifouling paints without organotin derivatives Type de document : texte imprimé Auteurs : K. Vallee-Rehel, Auteur ; B. Mariette, Auteur ; P. A. Hoarau, Auteur ; P. Guerin, Auteur ; V. Langlois, Auteur ; J. Y. Langlois, Auteur Année de publication : 1998 Article en page(s) : p. 55-63 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 667.9 Revêtements et enduits Résumé : Environmental concerns have led to a progressive withdrawal of antifouling paints containing organotin derivatives. Resanbio®, a cooperative research program, plans to develop new antifouling paints that are more compatible with living species. In the first stage, we studied specific acrylic polymers with a variable hydrophilic/hydrophobic balance and, in some cases, pendant hydrolyzable functions. To evaluate the ability of these materials for hydrolysis, biocides release, and erosion, test panels with formulated films were prepared and immersed in sea water. An analytical protocol was established to characterize the polymeric material, to reveal chemical reactions that occur during erosion and antifouling action, and to understand the influence of the resin chemical structure on the paint’s antifouling efficiency. The degradation of these binders was revealed by the appearance of a product resulting from the hydrolysis. This product was identified and quantified by GC-MS. The release of cuprous oxide as model molecule, due to its water solubility and biocide activity, was quantified by inductively coupled plasma. The different processes used are explained and illustrated by an example of an efficient, erodable, antifouling paint following 22 months of immersion. Note de contenu : - CHOICE AND CHARACTERIZATION OF THE CHEMICAL STRUCTURES - PERFECTING THE ANALYTICAL PROTOCOL : Choice of the coatings - Choice of the substrates - Analytical protocol - EVALUATION OF TWO NEW BINDERS WITHOUT ORGANOTIN DERIVATIVES : Hydrolysis and biocides release - Study of the effects of fillers - EVALUATION OF ANTIFOULING ACTIVITY ON NATURAL SITE Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17995 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
003549	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Photodegradation of water-based acrylic coatings containing silica / Alison M. Morrow in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 880 (05/1998)

[article]  inJOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 70, N° 880 (05/1998) . - p. 65-72 Titre : Photodegradation of water-based acrylic coatings containing silica Type de document : texte imprimé Auteurs : Alison M. Morrow, Auteur ; Norman S. Allen, Auteur ; Michele Edge, Auteur Année de publication : 1998 Article en page(s) : p. 65-72 Note générale : Bibliogr. Langues : Américain (ame) Tags : 'Peinture  eau'  'Dégradation  photochimique'  Feuil  'Méthacrylate  de  méthyle  copolymère'  'Acrylate  butyle  Adjuvant  Silice  'Mécanisme  réaction'  Durabilité  'Etude  expérimentale'  'Agent  matité' Index. décimale : 667.9 Revêtements et enduits Résumé : The durability of acrylic copolymer systems containing silica as a matting agent are investigated, with particular emphasis on the photodegradation process. The effects of the photodegradation process on the films are monitored chemically via reflectance FTIR spectroscopy and UV spectrophotometry and monitored physically via gloss levels, optical properties, film thickness, and film smoothness measurements of the cured film. The findings of this study show that as a result of photo-oxidation high levels of hydroperoxides are observed. In addition the FTIR results, which are discussed from a mechanistic point of view, indicate that functional group formations and crosslinking reactions which occur as a consequence of photodegradation, play a primary role. Therefore, this study suggests that silica can reduce the durability of acrylic based formulations and that the extent of this photodegradation appears to be dependent on silica type. Note de contenu : - EXPERIMENTAL : Materials - UV irradiation - Hydroperoxide analysis - FTIR analysis - Cured film properties - RESULTS AND DISCUSSION : Hydroperoxide analysis - FTIR analysis - Anhydride formation - Lactone formation - Acetophenone formation - Vinyl ketone formation - Vinyl formation - Crosslinking reactions - Cured film properties Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17996 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
003549	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Novel ambient temperature curable two-component waterborne silicone-acrylic coating / Nobuo Harui in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 880 (05/1998)

[article]  inJOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 70, N° 880 (05/1998) . - p. 73-77 Titre : Novel ambient temperature curable two-component waterborne silicone-acrylic coating Type de document : texte imprimé Auteurs : Nobuo Harui, Auteur ; Tetsuro Agawa, Auteur Année de publication : 1998 Article en page(s) : p. 73-77 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 667.9 Revêtements et enduits Résumé : Waterborne coatings are composed of resins containing hydrophilic functional groups. These groups usually remain in the coating film and can adversely affect film properties such as weatherability and resistance to water and alkali. We have developed a novel ambient temperature curable waterborne two-component system, in which the hydrophilic functional groups are consumed by the crosslinking reaction. The new coating system consists of a waterborne acrylic resin containing both tert-amino and carboxylic acid groups and a hardener containing both epoxy and alkoxysilyl groups. The waterborne silicone acrylic coatings provide superior film properties even if the acrylic resin has relatively low functional group content.In this paper we describe the crosslinking reaction mechanism and film properties using some acrylic resin types and paint formulations as examples Note de contenu : -EXPERIMENTAL MATERIALS : Model A od Acrylic resin solution type - Model B of WB resin type - Model C of acrylic resin solutio, type(used only for FTIR analysis) - Model D of WB (used only for FTIR analysis) - RESULTS AND DISCUSSION : Crosslinking mechanism - Film properties Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=18004 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
003549	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Pigment : measurement of performance / Juergen H. Braun in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 880 (05/1998)

[article]  inJOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 70, N° 880 (05/1998) . - p. 79-81 Titre : Pigment : measurement of performance Type de document : texte imprimé Auteurs : Juergen H. Braun, Auteur Année de publication : 1998 Article en page(s) : p. 79-81 Langues : Américain (ame) Index. décimale : 667.2 Colorants et pigments Résumé : Successes in the development of tests for pigment characterization have contributed greatly to sucesses of the industry. However, problems with the evaluation of performance have slowed progress in some areas of pigment development. Characterization involves measurement of indentifiable surface, structure, etc. Performance evaluations involve systems: paints and paint films. Complexity of the systems contributes to testing problems. Usually, performance tests try to simulate the real word. The closer to reality the test, the more convincing is its result. Test paints resemble, and often are, commercial paints. But commercial paints are formulated to minimize performance differences among ingredient batches or suppliers. The formulations are thus designed to be insensitive to the performance characteristics at stake. Model paints can be formulated for sensitivity to pigment performance but paint are convincing but not sensitive to the pigment performance. Data from a model paint is sensitive to the pigment but not convincing. Optical performance testing is least affected because of impressive instrumental progress. Hiding power, tinting strength and color can now be tested quantitatively , reliably, and reproducibly. Relative standard deviations of ± 5% are typical. Testing of durability, mechanical, and chemical performance has become a bottleneck to progress. Results can usually only be renked but not quantified and can rarely be reproduced to even modest satisfaction. Uncertainties, relative standard deviations, of 30-40% of value are typical. Problems are aggravated because the coatings industry overestimates the reliability and reproducibility of test results. Sill, it is not enough that a test reproduces well. In addition, it must be sensitive enough to reproduce small differences between similar pigment. Statistical evaluation of performance data would certainly help. Statistical quality control saves future expense but costs up-front money. Appreciation of statistics and paint laboratories and has yet to make significant inroads into manufacture and management. Note de contenu : - OPTICAL PERFORMANCE : Pigment strength - DURABILITY : Color pigments - Coatings - CHEMICAL AND MECHANICAL PERFORMANCE Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=18005 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
003549	-	Périodique	Bibliothèque principale	Documentaires	Disponible