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Titre : Polysilazanes : Binders that make a difference to surfaces Type de document : texte imprimé Auteurs : Yang Wang, Auteur ; Ralf Grottenmuller, Auteur ; Theresa Lorenz, Auteur Année de publication : 2019 Article en page(s) : p. 38-45 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Anticorrosifs
Anticorrosion
Essais accélérés (technologie)
Liants
Polysilazanes
Résistance au rayonnement ultraviolet
Résistance aux conditions climatiques
Revêtements -- Additifs:Peinture -- Additifs
Revêtements anti-graffitis
Revêtements organiques
Stabilité thermiqueIndex. décimale : 667.9 Revêtements et enduits Résumé : Polysilazanes are pre-ceramic polymers with a silicon-nitrogen backbone. In recent years they have developed as a high-performance binder in protective coatings for transportation vehicles, commercial and residential buildings, and industrial plants. This article reviews their structure-property relationship and highlights their performance in high-temperature, surface hardness, weathering and corrosion protection, and anti-graffiti applications. Note de contenu : - Synthesis and process
- Heat stability
- Surface Hardness
- Weather and corrosion resistance
- Anti-graffiti properties
- Coating uniformity
- Fig. 1 : Polymer structures for PHPS and OPSZ, where R is H, CH3, CH=CH2, other alkyl, or aryl groups
- Fig. 2 : Polymer structures for PHPS and OPSZ, where R is H, CH3, CH=CH2, other alkyl, or aryl groups
- Fig. 3 : The two curing routes for OPSZ, where R1 and R2 are H, CH3, CH=CH2, other alkyl or aryl groups
- Fig. 4 : Thermal stability evaluation of polysilazanes. Panel A shows the results of TGA for polysilazanes and two commercial silicone resins. All materials were dried at 120°C for four hours before TGA to simulate the thermal stability of their coatings. Panel B shows a stainless-steel exhaust pipe coated with both PHPS and OPSZ-based TBC. Panel C compares the visual appearance of a coated and uncoated exhaust pipe after pyrolysis at 1000°C for one hour in air. Panels B and C were obtained from the Royal Society of Chemistry and Motz et al. at the University of Bayreuth with permission
- Fig. 5 : Characteristics of surface hardness for PHPS and OPSZ coatings. Panel A displays data of surface hardness for PHPS coatings on silicon substrates cured at different temperatures. These coatings have a film thickness of 1–1.2 μm. The hardness was measured via pencil hardness (in blue bars), Martens hardness (orange dots), and indentation resistance (black dots). The dots lines are guides for the eyes. Panel B shows a reference scale of pencil hardness, Martens hardness, and indentation resistance by using a bare glass and PMMA substrate. Panel C shows the anti-scratching property for a ∼3 μm thick OPSZ coating in clearcoat applications, and Panel D shows a similar performance for pigmented coatings. Both pigmented coatings have 17 wt% of pigment loading, a film thickness of 10–12 μm, and the right panel has 40 wt% polysilazane as a binder. Crockmeter test was performed by using an Atlas AATCC Crockmeter with 3M Wet-or-Dry 281Q rubbing cloth
- Fig. 6 : Panel A shows two steel substrates after a 10-day water condensation test at a constant humidity of 50%. They have an electrochemically deposited white basecoat with a film thickness of 15–20 μm that partially covers the substrates. The substrate on the left has a 3–4 μm thick polysilazane-based clearcoat, while the one on the right does not. Panel B shows a similar comparison of coated and uncoated areas on a steel substrate after three days of HCl vapor exposure at room temperature [a beaker of HCl solution (37 vol%) was placed in the test chamber]. The coating thickness is about 2 μm
- Fig. 7 : Panel A is a comparison of contact angle and surface energy for polysilazanes and three common binder materials, including nitrocellulose lacquer, acrylates, and polyurethanes. Also shown in Panel A is the value of the polar and dispersive component of surface energy, and surface energy is a sum of the polar and dispersive component. Panel B shows water drop shapes and contact angle measurements on a neat polysilazane coating and on a formulated polysilazane coating with other surface additives
- Fig. 8 : Panel A is a marker test to demonstrate the ink repellency and easy-to-clean properties for a polysilazane based clearcoat. The inset shows the results after cleaning with a dry towel. Panel B is the result of an anti-graffiti test performed on a similar coating according to ASTM D6578, where level 1—dry cloth, level 2—mild detergent solution, level 3— limonene-based cleaner, level 4—isopropanol, and level 5—methyl ethyl ketone, n.c.—not cleanable
- Fig. 9 : Three-dimensional surface morphology scans for a bare steel substrate (A), an OPSZ-based clearcoat on a steel panel (B), and a similar coating on a glass substrate (C). The polysilazane coating thickness is about 15 μm and 10 μm on the steel and the glass substrate, respectively
- Table 1 : DIN/EN/ISO tests that OPSZ-based coatingsz have successfully passed
- Table 2 : OPSZ coating performance before and after artificial weathering and UV stability testEn ligne : https://drive.google.com/file/d/1KuEizt3Csd6O2NpcxCtM9uj10C1GeiwC/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=32737
in COATINGS TECH > Vol. 16, N° 6 (06/2019) . - p. 38-45[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 21023 - Périodique Bibliothèque principale Documentaires Disponible Polysiloxane coating technology : a review / Sangram Grosh in PAINTINDIA, Vol. LXIV, N° 6 (06/2014)
[article]
Titre : Polysiloxane coating technology : a review Type de document : texte imprimé Auteurs : Sangram Grosh, Auteur Année de publication : 2014 Article en page(s) : p. 51-58 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Alliages polymères
Anticorrosion
Epoxydes
Polyacryliques
Polymères aliphatiques
Polyuréthanes
Résistance à l'abrasion
Résistance à la salissure
Résistance aux conditions climatiques
Résistance chimique
Revêtements -- Propriétés mécaniques:Peinture -- Propriétés mécaniques
Revêtements anti-graffitis
Revêtements:Peinture
SiliconesLes silicones, ou polysiloxanes, sont des composés inorganiques formés d'une chaine silicium-oxygène (...-Si-O-Si-O-Si-O-...) sur laquelle des groupes se fixent, sur les atomes de silicium. Certains groupes organiques peuvent être utilisés pour relier entre elles plusieurs de ces chaines (...-Si-O-...). Le type le plus courant est le poly(diméthylsiloxane) linéaire ou PDMS. Le second groupe en importance de matériaux en silicone est celui des résines de silicone, formées par des oligosiloxanes ramifiés ou en forme de cage (wiki).Index. décimale : 667.9 Revêtements et enduits Résumé : Polysiloxane topcoats offer unique properties such as long life expectancy, low maintenance cost, superior weatherability, good corrosion protection, fast dry to handle properties, low VOC content, non-isocyanate regulation compliance and extreme durability.
Many specifiers and applicators have utilized the cost effectiveness and life to first maintenance of the Siloxane two coat systems (i.e. zinc rich epoxy or inorganic zinc rich primer) in preference to the use of three or more coat systems.
Having Si-O bonds, it provides excellent resistant properties. Organic modification such as epoxy/acrylic polysiloxane provides optimum performance as well as reduced application cost. It has excellent gloss retention as compared to state of the art aliphatic polyurethane coatings.Note de contenu : - Why are siloxane coatings unique ?
- The chemistry of epoxy polysiloxane and acrylic polysiloxane
- The lifetime of a coating system
- Wheathering performance
- Gloss retention in QUV-A versus natural exposure
- Anti-corrosion performance
- Abrasion/anti-graffiti/chemical resistance
- Dirt pick up resistance
- Mechanical properties
- Flexibility
- Surface tolerance
- Formulation development
- The futureEn ligne : https://drive.google.com/file/d/1z-ev_f8dc_EOR3nbOWfgFCe4Ako2oy84/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=21787
in PAINTINDIA > Vol. LXIV, N° 6 (06/2014) . - p. 51-58[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 16458 - Périodique Bibliothèque principale Documentaires Disponible Predicting in-service weatherability of automotive coatings : A new approach / David R. Bauer in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 69, N° 864 (01/1997)
[article]
Titre : Predicting in-service weatherability of automotive coatings : A new approach Type de document : texte imprimé Auteurs : David R. Bauer, Auteur Année de publication : 1997 Article en page(s) : p. 85-96 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Automobiles -- Revêtements:Automobiles -- Peinture
Délaminage
Durée de vie (Ingénierie)
Photodétérioration
Résistance aux conditions climatiquesIndex. décimale : 667.9 Revêtements et enduits Résumé : The prediction of long-term weatherability of coatings has always been a difficult task. This task has been made significantly more difficult by the recent, rapid changes in coatings technology. Conventional weathering protocols which rely on observation of appearance changes after outdoor or laboratory exposures have not always been successful in anticipating in-service failures. This paper discusses the reason for this and describes a new approach for estimating in-service weatherability in coatings. The formalism begins by identifying specific failure modes and developing time-to-failure models which are based on fundamental studies of the chemistry and physics of failure. The statistical variation of the key material, process, and exposure parameters in the failure model are described in terms of distribution functions. Since photooxidation plays a critical role in most weathering issues, a specific distribution function for exposure harshness is estimated that can be used to describe the variation in photooxidation rate under actual in-service conditions. By combining a specific failure model with in-service variations in the key parameters, it is possible to estimate in-service failure rates as a function of material and processing variables, thus, allowing for improved risk assessment of any proposed material or processing change. The formalism also provides clearer direction in the design and use of specific laboratory and outdoor exposures in predicting performance. The method is illustrated by deriving distributions of time-to-failure based on two different hypothetical mechanisms of photo-induced coating delamination. Note de contenu : - ESTIMATION OF AN EXPOSURE DISTRIBUTION FUNCTION
- DEVELOPMENT OF MODELS OF TIME-TO-FAILURE : Constant UV light transmission - Determination resulting from loss of UVAPermalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=18077
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Code-barres Cote Support Localisation Section Disponibilité 003533 - Périodique Bibliothèque principale Documentaires Disponible Preparation of an ionic/nonionic polyurethane-silicone dispersion (PUSD) with a high solid content and low viscosity using complex soft segments / Xiaoli Wei in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 15, N° 6 (11/2018)
[article]
Titre : Preparation of an ionic/nonionic polyurethane-silicone dispersion (PUSD) with a high solid content and low viscosity using complex soft segments Type de document : texte imprimé Auteurs : Xiaoli Wei, Auteur ; Faxing Zhang, Auteur Année de publication : 2018 Article en page(s) : p. 1229-1237 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Copolymère silicone-uréthane
Dispersions et suspensions
Dispersions et suspensions -- Stabilité
Haut extrait sec
Hydrophobie
Particules -- Morphologie
Résistance aux conditions climatiques
Revêtements en phase aqueuse
Rhéologie
Taille des particulesIndex. décimale : 667.9 Revêtements et enduits Résumé : A series of ionic/nonionic polyurethane-silicone dispersions (PUSDs) with a high solid content and low viscosity were prepared using isophorone diisocyanate as the hard segment, polytetrahydrofuran polyether diol (PTMG) and polysiloxane diol (PESI) as the complex soft segments and an ionic/nonionic low molecular weight polyether diol (DPSA) as the hydrophilic, chain-extending agent. The morphologies and rheological properties of the ionic/nonionic PUSD were examined using particle-size, TEM, and viscosity analyses. The hydrophobic and mechanical properties of the dispersions were also tested. It was found that under the conditions of a constant NCO/OH ratio (2/1) and weight percentage of DPDA (6%), the PUSD dispersions with higher PESI contents possessed higher average particle diameters and wider particle-size distributions. Particles in the PUSD dispersions are generally spherical and have a typical core–shell structure due to the use of complex soft segments. However, the solid content of the ionic/nonionic PUSD increased first and then decreased as the weight ratio of PESI to PTMG increased. When the ratio ranged from 4/10 to 6/10, the max solid content of the ionic/nonionic PUSD reached up to 58%, but the viscosity of the PUSD was less than 400 mPa.s−1. Meanwhile, the water contact angle of the films increased due to the formation of a crosslinking structure on the side of the PUSD macromolecule, and when the weight ratio of PESI to PTMG varied from 3/10 to 7/10, the water contact angle of the films increased from 48.3° to 72.3°. In addition, both the freeze-thaw and thermal stabilities of the PUSD dispersions were enhanced as the weight ratio of PESI to PTMG increased. The PUSD coating had good mechanical properties as well. Note de contenu : - EXPERIMENTAL : Materials - Synthesis of the polyurethane-silicone dispersions (PUSDs) - Characterization
- RESULTS AND DISCUSSION : Average particle diameter and distribution of the dispersions - Particle morphology of the dispersions - Rheology of the dispersions - The stability of the dispersions - The hydrophobic properties of the PUSD films - The mechanical properties of the PUSD coatingDOI : 10.1007/s11998-018-0063-6 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-018-0063-6.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=31333
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Code-barres Cote Support Localisation Section Disponibilité 20388 - Périodique Bibliothèque principale Documentaires Disponible Principles of accelerated weathering : evaluations of coatings / Mark Nichols in COATINGS TECH, Vol. 17, N° 1 (01/2020)
[article]
Titre : Principles of accelerated weathering : evaluations of coatings Type de document : texte imprimé Auteurs : Mark Nichols, Auteur Année de publication : 2020 Article en page(s) : p. 18-25 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Essais accélérés (technologie)
Photo-oxydation
Résistance aux conditions climatiques
Revêtements -- Détérioration:Peinture -- DétériorationIndex. décimale : 667.9 Revêtements et enduits Résumé : One of paint’s most important attributes is its ability to maintain performance for an extended period of time in its intended service environment. That environment may be an interior wall in a single family home, the outside of an underground pipeline, or the exterior of a vehicle. The service environment is different in all three cases, but the ability to maintain the paint’s functions—aesthetics, adhesion, corrosion protection, and mechanical performance—is still required.
Objects that predominantly reside outdoors are subjected to one of the most challenging service environments for coatings. Exposure to solar radiation, temperature fluctuations, rain, snow, and environmental fallout (acid rain), challenge the performance of most coatings. Examples of painted objects that are exposed to such environments include automobiles, aircraft, infrastructure (bridges and roads), houses, and buildings. To achieve long-term performance, exterior coatings require resistance to degradation by UV radiation, resistance to hydrolysis, and resistance to erosion by rain and snow.
The durability of a coating is typically assessed by exposing it at selected outdoor locations to quantify the coating’s real-world performance. While natural exposure outdoors is a reliable method of assessment, natural exposure provides little acceleration. A coating that performs acceptably after five years of Florida exposure means that the coating will survive five years of exposure in Florida, but this says nothing about its performance after 5.5 years or 10 years. It does mean that the coating may survive longer than five years in a less harsh environment, but the failure mode may change, as environmental loads can vary dramatically from region to region.1 Thus, it is impractical to develop coatings using natural outdoor exposure as a method to assess their long-term durability, as product development time cycles are not compatible with test methods that take five-plus years to perform.
Coating formulators, therefore, rely heavily on accelerated weathering tests to develop and optimize coating formulations. Accelerated weathering tests attempt to degrade a coating at a faster rate than that which occurs during natural exposure. However, to be reliable and useful, the increased rate of degradation must not sacrifice the accuracy of the results, meaning the correlation between accelerated weathering results and natural weathering results must be quite high. Unreliable results produced quickly are not useful, and can potentially be quite damaging to a company’s reputation and bottom line. The bulk of this article will discuss the science behind paint degradation and the various methods used to assess paint weatherability.Note de contenu : - Paint degradation chemistry
- Coating stabilization
- Natural weathering testing
- Accelerated weathering tests
- Post-exposure testing
- Correlation to outdoor exposure
- Fig. 1 : Reaction schematic for photooxidation in polymers
- Fig. 2 : Painted panels in exposure racks in south Florida. (Upper) automative coatings exposed at 5° south and (lower) architectural coatings exposed at 90° south
- Fig. 3 : QUV accelerated weathering chamber
- Fig. 4 : The spectral power distribution of UV-A and UV-B bulbs used in a QUV accelerated weathering instrument. The spectrum of sunlight is also shown as a reference
- Fig. 5 : Weather-Ometer accelerated weathering instrument
- Fig. 6 : Spectral power distribution of xenon-arc lamps filtered with boro/boro and quartz/boro filter combinations. Sunlight spectrum also shown for reference ; SPD of sunlight, Righlight, and boro/boro filtered light on log scale to demonstrate the fidelity of the match between sunlight and Righlight filter combination
- Fig. 7 : Fresnel-type accelerated outdoor exposure device
- Table 1 : Accelerated weathering test conditionsEn ligne : https://drive.google.com/file/d/1WnhA_OsUarcCoYy3KIMGK5ZYelbOuCni/view?usp=share [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=33600
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Code-barres Cote Support Localisation Section Disponibilité 21512 - Périodique Bibliothèque principale Documentaires Disponible Protection against cold and foul weather in TEXTILES A USAGES TECHNIQUES (TUT), N° 43 (1er trimestre 2002)
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PermalinkUn revêtement acrylique incolore en poudre pour l'équipement automobile / Holger Schmidt in EUROPEAN COATINGS JOURNAL (ECJ), N° 9/94 (09/1994)
PermalinkPermalinkService life prediction of colour retention for PVDF architectural coatings with organic pigments / Kurt A. Wood in SURFACE COATINGS INTERNATIONAL. PART B : COATINGS TRANSACTIONS, Vol. 89, B3 (09/2006)
PermalinkShorter processes and improved quality in INTERNATIONAL SURFACE TECHNOLOGY (IST), Vol. 11, N° 3 (2018)
PermalinkSignificantly improved electrical conductivity / Jürgen Leßlhumer in EUROPEAN COATINGS JOURNAL (ECJ), (04/2023)
PermalinkSilicone intermediate for weather-resistant coatings / Birgit Richter in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 202, N° 4569 (02/2012)
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PermalinkStabilising pearlescent pigments / Ulrich Schmidt in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 197, N° 4519 (12/2007)
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