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Critical role of particle/polymer interface in photostability of nano-filled polymeric coatings / Xiaohong Gu in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 9, N° 3 (05/2012)
[article]
Titre : Critical role of particle/polymer interface in photostability of nano-filled polymeric coatings Type de document : texte imprimé Auteurs : Xiaohong Gu, Auteur ; Guodong Chen, Auteur ; Minhua Zhao, Auteur ; Stephanie S. Watson, Auteur ; Tinh Nguyen, Auteur ; Joannie W. Chin, Auteur ; Jonathan W. Martin, Auteur Année de publication : 2012 Article en page(s) : p. 251-267 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Essais accélérés (technologie)
Interfaces (Sciences physiques)
Nanoparticules
Oxyde de zinc
Photodétérioration
Polyuréthanes
Résistance au rayonnement ultraviolet
Revêtements en phase aqueuse:Peinture en phase aqueuseIndex. décimale : 667.9 Revêtements et enduits Résumé : Nanoparticle-filled polymeric coatings have attracted great interest in recent years because the incorporation of nanofillers can significantly enhance the mechanical, electrical, optical, thermal, and antimicrobial properties of coatings. Due to the small size of the fillers, the volume fraction of the nanoparticle/polymer interfacial area in nano-filled systems is drastically increased, and the interfacial region becomes important in the performance of the nano-filled system. However, techniques used for characterizing nanoparticle/polymer interfaces are limited, and thus, the mechanism by which interfacial properties affect the photostability and the long-term performance of nano-filled polymeric coatings is not well understood. In this study, the role of the nanoparticle/polymer interface on the ultraviolet (UV) stability of a nano-ZnO-filled polyurethane (PU) coating system was investigated. The effects of parameters influencing the particle/polymer interfacial properties, such as size, loading, surface modification of the nanoparticles, on photodegradation of ZnO/PU films were evaluated. The nature of the interfacial regions before and after UV exposures were characterized by atomic force microscopy (AFM)-based techniques. Results have shown that the interfacial properties strongly affect chemical, thermo-mechanical, and morphological properties of the UV-exposed ZnO/PU films. By combining tapping mode AFM and novel electric force microscopy (EFM), the particle/polymer interfacial regions have been successfully detected directly from the surface of the ZnO/PU films. Further, our results indicate that ZnO nanoparticles can function as a photocatalyst or a photostabilizer, depending on the UV exposure conditions. A hypothesis is proposed that the polymers in the vicinity of the ZnO/PU interface are preferentially degraded or protected, depending on whether ZnO nanoparticles act as a photocatalyst or a photostabilizer in the polymers. This study clearly demonstrates that the particle/polymer interface plays a critical role in the photostability of nano-filled polymeric coatings. Note de contenu : - EXPERIMENTAL : Materials and specimen preparation - High UV radiant laboratory exposure - Measurements
- RESULTS AND DISCUSSION : Thermo-mechanical properties of nano-filled coatings and their relationship with interfacial interactions - Detecting embedded nanoparticle/polymer interface using AFM-based techniques - Role of nanoparticle/polymer interface in photostability of nano-filled polymeric coatingsDOI : 10.1007/s11998-011-9326-1 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-011-9326-1.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15950
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 9, N° 3 (05/2012) . - p. 251-267[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 14188 - Périodique Bibliothèque principale Documentaires Disponible Cross-linked polymers for aqueous finishing. Binders crosslinked with polyaziridin. Part. 1 : Behaviour of polyurethane in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 92, N° 3 (05-06/2008)
[article]
Titre : Cross-linked polymers for aqueous finishing. Binders crosslinked with polyaziridin. Part. 1 : Behaviour of polyurethane Type de document : texte imprimé Année de publication : 2008 Article en page(s) : p. 96-102 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Finition
Formulation (Génie chimique)
Liants en phase aqueuse
Polyaziridine
Polyuréthanes
Résistance à l'abrasion
Réticulants
Revêtements en phase aqueuse
Revêtements organiques
Solidité de la couleurIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Aqueous finishing emerges as an alternative to solvent based finishes, which have to be limited due to their toxicity, negative effects on the environment and in terms of safety. It is necessary, in order to be able to introduce aqueous systems progressively, to use cross-linkers that react with polymers. Otherwise, it is not possible to obtain the physical properties required for most leather goods. The present study aims to look into the behaviour of polyurethane binders cross-linked with polyaziridine : the amount of cross-linker used, the type of polymer employed, the type of tannage and retannage effected and the evolution of the reaction over time.
A comparison of results shows that the type of tannage and retannage, as well as the physical characteristics of the polyurethane used are influential factors in the behaviour of polyurethane binders cross-linked with polyaziridine. Different amounts of polyaziridine are needed with regard to the type of tannage and retannage effected and to the physical characteristics of the polyurethane used.Note de contenu :
- Chemical products
- Methodology
- Table 1 : Physical characteristics of the polyurethane binders
- Table 2 : Coating formulation
- Table 3 : Results of colour fastness to dry rubbing
- Table 4 : Results of colour fastness to wet rubbingEn ligne : https://drive.google.com/file/d/1RXtnSVbt5AcIo_FcnmplkihJ5LMM34iP/view?usp=share [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38953
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 92, N° 3 (05-06/2008) . - p. 96-102[article]Crosslink density and cure window of oligourethane diol/melamine high-solids coatings / M. Yaseen in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 879 (04/1998)
[article]
Titre : Crosslink density and cure window of oligourethane diol/melamine high-solids coatings Type de document : texte imprimé Auteurs : M. Yaseen, Auteur ; K. V. S. N. Raju, Auteur ; Syed Haseebuddin, Auteur Année de publication : 1998 Article en page(s) : p. 35-42 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Formaldéhyde
Haut extrait sec
MélamineLa mélamine, de nom chimique 1,3,5-triazine-2,4,6-triamine, est parfois dénommée cyanuramide ou cyanurotriamine. Sa formule brute est C3H6N6.
Les "résines mélamine-formaldéhyde" ou "mélamine-formol" (sigle MF) sont appelées "mélamine" dans le langage courant. Elles font partie de la famille des aminoplastes qui regroupe des résines thermodurcissables aminées, issues d'un comonomère tel l'urée ou la mélamine, parfois le thiocarbamide, le cyanamide hydrogène ou le dicyandiamide ; le second comonomère étant le formaldéhyde.
Oligomères
Polyols
Polyuréthanes
Réticulation (polymérisation)
RevêtementsIndex. décimale : 667.9 Revêtements et enduits Résumé : Oligourethane diols were crosslinked with melamine formaldehyde, and their crosslink density was determined by using an equilibrium swelling method. In formulations containing primary or secondary hydroxylated diol the major part of the crosslinker is consumed by trans-etherification reactions and self-condensation. The aromatic nature of TDI imparts rigidity while the aliphatic IPDI results in flexibility of the backbone chain of oligomer. The profile of cure schedules has been determined in the form of a cure window which measures the extent of reaction in terms of crosslink density as a function of bake temperature. The experimentally determined properties like tensile strength and MEK rub-resistance have been taken into consideration for fixing the lower and upper limits of XLD in designing the cure windows of individual coating formulations. The baking schedules of coatings have also been expressed in the form of nominal and true cure windows. Note de contenu : - INTRODUCTION : Crosslinking reactions between polyols and melamine - Crosslink density - Techniques for the determination of crosslink density - Curing aspects of high-solids coatings - Cure window
- EXPERIMENTAL : Oligourethane diol - Melamine crosslinker - Coating formulation - Preparation of free film of cured resin - Procedure for the determination of crosslink density - Calculation of crosslink density - Tensile properties - Solvent (MEK) rub resistance
- DISCUSSION : Effect of bake temperature and crosslinker content of XLD - Effect of oligourethane diol on crosslink density - Influence of isocyanates used in oligourethane diols - Cure schedules - Baking schedules in terms of cure window - Nominal and true cure windowPermalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17969
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 70, N° 879 (04/1998) . - p. 35-42[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 003548 - Périodique Bibliothèque principale Documentaires Disponible Crosslinked polyurethane–epoxy hybrid emulsion with core–shell structure / Wen Xiufang in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 7, N° 3 (05/2010)
[article]
Titre : Crosslinked polyurethane–epoxy hybrid emulsion with core–shell structure Type de document : texte imprimé Auteurs : Wen Xiufang, Auteur ; Ruilian Mi, Auteur ; Huang Ying, Auteur ; Jiang Cheng, Auteur ; Pi Pihui, Auteur ; Zuohru Yang, Auteur Année de publication : 2010 Article en page(s) : p. 373-381 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Epoxydes
Polyuréthanes
Réticulation (polymérisation)
Revêtements en phase aqueuse:Peinture en phase aqueuseIndex. décimale : 667.9 Revêtements et enduits Résumé : An epoxy resin was used to prepare crosslinked polyurethane hybrid emulsion through the blocked NCO prepolymer mixing process. Due to their hydrophobicity, the amine chain extender, blocked –NCO, and epoxy are located inside the emulsion particles. Thus, the crosslinking reaction occurs mostly in the interior of the particles. In this way, the crosslinking density of the resin is increased without the use of solidifying agents or heating during film formation, and the stability of the emulsions remains uninfluenced. The effects of the type of amine chain extender and the type, dosage, and addition mode of the epoxy resin were studied in terms of mechanical properties and swelling properties in water and toluene of the cast films. Additionally, the stability of the single-pack hybrid emulsion was studied. The results showed that the sample prepared with diethylene triamine had good stability, chemical resistance, and high mechanical strength. The modulus and water resistance of the films increased with the epoxy resin content, which could reach 20 wt %. The type of amine chain extender affected the stability of the emulsions significantly. The molar ratio of NH/NCO at 1:1 led to the best film performance. The optimal temperature of the chain-extension reaction was approximately 80°C. The hybrid emulsions could be stored for at least 6 months without apparent performance changes. DOI : 10.1007/s11998-009-9196-y En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-009-9196-y.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=9816
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 7, N° 3 (05/2010) . - p. 373-381[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 012381 - Périodique Bibliothèque principale Documentaires Disponible Crosslinker blends in two-component waterborne polyurethane / William O. Buckley in EUROPEAN COATINGS JOURNAL (ECJ), N° 10/97 (10/1997)
[article]
Titre : Crosslinker blends in two-component waterborne polyurethane Type de document : texte imprimé Auteurs : William O. Buckley, Auteur ; Marianne K. Groeneveld, Auteur Année de publication : 1997 Article en page(s) : p. 942-946 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Isocyanates
Liants
Polyols
Polyuréthanes
Réticulants
Revêtements bi-composant:Peinture bi-composant
Revêtements en phase aqueuse:Peinture en phase aqueuseIndex. décimale : 667.9 Revêtements et enduits Résumé : This paper describes waterborne two-component polyurethane coatings based on novel polyol dispersions that meet or exceed the performance levels of typical solvent based systems. These coatings have the key advantage of using isocyanate crosslinkers normally employed in solvent borne systems without any modification or chemical change to the isocyanates being necessary. Using the new polyol dispersion, the isocyanates can be simply stirred in by hand to achieve a homogeneous dispersion ready for application. The polyols can be crosslinked with either single isocyanate crosslinkers or with crosslinker blends. This paper demonstrates that blending several of these isocyanates allows for wide formulation latitude in the resultant waterborne coatings. Note de contenu : - Appearance
- Hardness
- Adhesion
- Solvent resistance
- Impact resistancePermalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=11436
in EUROPEAN COATINGS JOURNAL (ECJ) > N° 10/97 (10/1997) . - p. 942-946[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 002532 - Périodique Bibliothèque principale Documentaires Disponible Crosslinking of waterborne polyurethane dispersions / Valentino J. Tramontano in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 67, N° 848 (09/1995)
PermalinkLe cuir vivant / Bayer / Leverkusen [Allemagne] : Bayer (1974)
PermalinkPermalinkCure behavior of silicone-epoxies and urethane modified acrylates in interpenetrating polymer networks / L. Price in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 68, N° 854 (03/1996)
PermalinkPermalinkPermalinkCuring polyurethane problems / Daniels Len in ADHESIVE TECHNOLOGY, Vol. 15, N° 4 (12/1998)
PermalinkCustomized soft-touch thanks to threefold process integration in KUNSTSTOFFE INTERNATIONAL, Vol. 104, N° 3 (03/2014)
PermalinkCutting-edge food packaging a safe bet / Julia Fraunhoffer in ADHESION - ADHESIVES + SEALANTS, Vol. 14, N° 3/2017 (2017)
PermalinkCutting-edge solutions for auto refinish : high value polyurethane coatings / Kumar Lyer in PAINTINDIA, Vol. LXVII, N° 8 (08/2017)
PermalinkPermalinkPermalinkDecorative auto parts in one step / Frank Rothbarth in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 203, N° 4590 (11/2013)
PermalinkPermalinkDegradable polyurethane based on triblock polyols composed of polypropylene glycol and e-caprolactone for marine antifouling applications / Jinghua Yao in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 17, N° 4 (07/2020)
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