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Technical highlights from the 2022 American Coatings Conference / Leo J. Procopio in COATINGS TECH, Vol. 19, N° 5 (05-06/2022)
[article]
Titre : Technical highlights from the 2022 American Coatings Conference Type de document : texte imprimé Auteurs : Leo J. Procopio, Auteur Année de publication : 2022 Article en page(s) : p. 16-23 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Agents coalescents
Composés amphiphiles
Dioxyde de titane
Ester de phosphate
Esters de glycidyle
Lévulinates
LignineLa lignine est un des principaux composants du bois, avec la cellulose, l'hémicellulose et des matières extractibles. La lignine est présente principalement dans les plantes vasculaires et dans quelques algues. Ses principales fonctions sont d'apporter de la rigidité, une imperméabilité à l'eau et une grande résistance à la décomposition. Toutes les plantes vasculaires, ligneuses et herbacées, fabriquent de la lignine. Quantitativement, la teneur en lignine est de 3 à 5 % dans les feuilles, 5 à 20 % dans les tiges herbacées, 15 à 35 % dans les tiges ligneuses. Elle est moindre pour les plantes annuelles que pour les vivaces, elle est maximum chez les arbres. La lignine est principalement localisée entre les cellules (voir parois pectocellulosiques), mais on en trouve une quantité significative à l'intérieur même de celles-ci. Bien que la lignine soit un réseau tridimensionnel hydrophobe complexe, l'unité de base se résume essentiellement à une unité de phénylpropane. La lignine est le deuxième biopolymère renouvelable le plus abondant sur la Terre, après la cellulose, et, à elles deux, elles cumulent plus de 70 % de la biomasse totale. C'est pourquoi elle fait l'objet de recherches en vue de valorisations autres que ses utilisations actuelles en bois d'œuvre et en combustible.
Voie de biosynthèse : La lignine est une molécule dont le précurseur est la phénylalanine. Cet acide aminé va subir une cascade de réactions faisant intervenir une dizaine de familles d'enzymes différentes afin de former des monolignols. Ces enzymes sont : phénylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), 4-coumarate:CoA ligase (4CL), hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase (HCT), p-coumarate 3-hydroxylase (C3H), caffeoyl-CoA o-methyltransferase (CCoAOMT), cinnamoyl-CoA reductase (CCR), ferrulate 5-hydroxylase (F5H), caffeic acid O-methyltransferase (COMT) et cinnamyl alcohol deshydrogenase (CAD). Dans un certain nombre de cas, des aldéhydes peuvent également être incorporés dans le polymère.
Matériaux -- Propriétés fonctionnelles
Nanotubes
Piégeur de formaldéhyde
Polymères -- Détérioration
Revêtements (produits chimiques)
Revêtements (produits chimiques):Peinture (produits chimiques)
Revêtements -- Additifs
Revêtements organiques
VirucidesIndex. décimale : 667.9 Revêtements et enduits Résumé : The entire North American paint and coatings industry met in person for the first time in four years during the American Coatings Show and Conference, held in Indianapolis April 5–7. The last in-person exhibit and conference were held in 2018—two years prior to the COVID-19 pandemic. By all accounts, the 2022 conference and exhibit were overwhelming successes. People in the industry have been missing the in-person interaction for more than two years due to pandemic-related restrictions and were ready to get together to discuss all things concerning paint and coating. The American Coatings Conference consisted of nearly 760 attendees, all engaging in 90 presentations describing the latest advances in coatings technology.
This article includes technical highlights from many of the sessions, which were held concurrently in four tracks. Further details can be found in the papers available in the proceedings of the conference. Some papers will also be published in future issues of CoatingsTech after peer review. The papers highlighted in this article will be presented according to some overarching themes that they addressed : Sustainability, Functional Coatings, Paint Fundamentals, and Additive Technologies. These brief summaries will hopefully serve to interest the reader to seek out the full papers and learn more about the thought-provoking topics presented during the conference.Note de contenu : - SUSTAINABILITY : The use of levulinates as coalescing agents in water-based coatings - Lignin as a raw material for production of biobased resins - Aliphatic glycidyl ethers as crosslinkers for high-performance NISO coatings - Improving the odds of success using a benign-by-design approach to product development
- FUNCTIONAL COATINGS : Creating functinal coatings with formaldehyde-scavenging additives - The use of single-walled carbon nanotubes in coatings colorants - Key considerations for functional virucidal paints
- PAINT FUNDAMENTALS : Separating the effects of TiO2 dispersion and photoactivity on paint durability - Improving application experience and applied hide for professional paints via additives optimization
- ADDITIVE TECHNOLOGIES : reactive epoxy emulsifier for high-performance waterborne epoxy coatings - Improving water resistance of water-based coatings using reactive surfactants - Fluoro-free and silicone-free blocking resistance additives for waterborne coatings
- Fig. 1 : Structures of levulinic acid and derivatives
- Fig. 2 : Aliphatic tetrafunctional glycidyl ether based on the epoxidation of sorbitol
- Fig. 3 : Reactions of formaldehyde scavenger tris(hydroxymethyl)aminomethane with formaldehyde to form mono- and bis-oxazolidines
- Fig. 4 : Reaction pathways leading to the degradation of polymer in a coating. TiO2 *signifies TiO2 in an excited electronic state
- Fig. 5 : General structure of amphiphilic phosphate esters and reaction scheme showing their synthesis from alcoholsEn ligne : https://drive.google.com/file/d/12b3ve5O2irEaTk0-Wue90XrdScFIAtWS/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37861
in COATINGS TECH > Vol. 19, N° 5 (05-06/2022) . - p. 16-23[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 23507 - Périodique Bibliothèque principale Documentaires Disponible The search for improved alternatives in epoxy toughening / William Starner in ADHESIVES & SEALANTS INDUSTRY (ASI), Vol. 16, N° 6 (06/2009)
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Titre : The search for improved alternatives in epoxy toughening : New research shows the performance benefits of glycidyl esters Type de document : texte imprimé Auteurs : William Starner, Auteur Année de publication : 2009 Article en page(s) : p. 19-23 Langues : Américain (ame) Catégories : Adhésifs -- Additifs
Adhésion
Bisphénol A
Epoxydes
Esters de glycidyle
Formulation (Génie chimique)
Plastifiants
Transition vitreuse
ViscositéIndex. décimale : 668.3 Adhésifs et produits semblables Résumé : The test results demonstrate that the modifiers examined in this study, whether adducted or glycidated, provide significant advantages in performance properties compared to the unmodified control formulation. Results also showed that glycidyl ester modifiers provide significant advantages over the bisphenol A epoxy adducts in their ability to reduce processing viscosity without sacrificing adhesive or toughener performance.
Other conclusions of the study include the following : The glycidyl ester modifiers are lower in viscosity and yield lower formulation mix viscosities than the industry benchmark.
Selection of the proper glycidyl ester will allow for higher Tg and desired adhesive and toughener performance.
The end group functionality appears to affect compatibility in the cured epoxy matrix, which in turn affects Tg. Glycidyl esters exhibit less compatibility than epoxy adducts and thus give higher Tg.
The study shows that adhesive properties are affected by the polymer backbone. Both polyester backbones and butadiene/acrylonitrile copolymer backbones provide good adhesion.
The best adhesion performance was achieved with glycidyl ester modifiers prepared using a CTBN.
No individual modifier will yield optimal results in all applications. The results of this study, however, demonstrate that there are newer alternatives with the potential to deliver better performance results in applications in which a low-viscosity modifier is needed. Glycidyl esters offer a number of advantages over the industry benchmark and, therefore, should be considered as the market continues to move toward products that are both energy- and cost-efficient.Note de contenu : - STUDY DESCRIPTION
- MODEL FORMULA AND TEST PROTOCOL
- RESULTS AND DISCUSSION : Bisphenol A epoxy adducted modifiers - Glycidyl ester modifiers
- FIGURES : 1. SEM micrographs of unmodified vs. modified cured epoxy formulations - 2. Backbone and end group structures
- TABLES : 1. Epoxy formulations using bisphenol A epoxy adducted esters as modifiers - 2. Epoxy formulations using glycidyl esters as modifiersEn ligne : http://www.adhesivesmag.com/articles/88175-the-search-for-improved-alternatives- [...] Format de la ressource électronique : Web Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=25906
in ADHESIVES & SEALANTS INDUSTRY (ASI) > Vol. 16, N° 6 (06/2009) . - p. 19-23[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 011389 - Périodique Bibliothèque principale Documentaires Disponible Waterborne 2K polyurethane topcoats / Cédric Le Fevere de Ten Hove in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 203, N° 4584 (05/2013)
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Titre : Waterborne 2K polyurethane topcoats Type de document : texte imprimé Auteurs : Cédric Le Fevere de Ten Hove, Auteur ; Christophe Steinbrecher, Auteur ; Denis Heymans, Auteur Année de publication : 2013 Article en page(s) : p. 30-33 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Automobiles -- Revêtements:Automobiles -- Peinture
Diluants
Esters de glycidyle
Polyacryliques
Polyols
Polyuréthanes
Revêtements
Revêtements -- Finition
Revêtements bi-composant
Revêtements en phase aqueuse:Peinture en phase aqueuseIndex. décimale : 667.9 Revêtements et enduits Résumé : Conventional acrylic polyols for waterborne polyurethane topcoats are usually prepared via a solution polymerisation process, which is then followed by solvent removal. Thereafter, the resins are dispersed in water. This lengthy process requires high energy levels to distil the solvent and favours side reactions that negatively affect performance of the derived coatings.
This work demonstrates that high quality acrylic resins can be prepared in a very convenient, simple, one step process using glycidyl esters as reactive diluent. Resins were prepared with a solvent level of about 10% with either glycicyl neodecanoate or a novel glycidyl neoanoate. The latter provides resins with a higher glass transition temperature and, therefore, coatings with a faster hardness development rate. Derived 2K polyurethane clearcoats combine properties, such as excellent appearance, durability and drying speed. Further, glycidyl esters reactive diluents were combined with lower molecular weight polyesters to attempt to eliminate the need for any solvent during acrylics polymerisation.Note de contenu : - THE POPPING OR BLISTERING ISSUE
- ACRYLIC AND HYBRID SECONDARY DISPERSIONS
- GLYCIDYL ESTERS-BASED ACRYLIC POLYOLS
- GLYCIDYL ESTER-BASED STAR POLYESTERS AND DERIVED HYBRIDS : Experimental part : polyols and clearcoats formulations and applications - Experimental part : clearcoats performanceEn ligne : https://drive.google.com/file/d/1mIwZ4gp9hFaXa_zZ1N1NZz7of6v4LlS-/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=18549
in POLYMERS PAINT COLOUR JOURNAL - PPCJ > Vol. 203, N° 4584 (05/2013) . - p. 30-33[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15080 - Périodique Bibliothèque principale Documentaires Disponible