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A novel chromium-free tanning process based on in-situ melamine-formaldehyde oligomer condensate / Xue Bai in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CVIII, N° 11 (11/2013)
[article]
Titre : A novel chromium-free tanning process based on in-situ melamine-formaldehyde oligomer condensate Type de document : texte imprimé Auteurs : Xue Bai, Auteur ; Jinming Chang, Auteur ; Chen Yi, Auteur ; Haojun Fan, Auteur ; Bi Shi, Auteur Année de publication : 2013 Article en page(s) : p. 404-410 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Analyse thermique
Azote total
Carbone organique total
Condensation
Copolymère mélamine-Formaldéhyde
Cuirs et peaux de chèvres
Microscopie électronique à balayage
Oligomères
Oligomères conjugués
Point isoélectriqueEn biochimie, le point isoélectrique (pI) ou potentiel hydrogène isoélectrique (pHI) est le pH auquel une molécule est sous forme d'ion mixte ou, en physico-chimie, le pH d'une solution aqueuse dans laquelle un solide existe sous un potentiel électrique neutre.
En physico-chimie : Selon Bolger, le caractère acide ou basique d'une surface s'exprime par son point isoélectrique " Is ou IEPS (Iso Electric point for the surface) " ou point de charge nulle " PCN ou PZC (Point of Zero Charge) ", défini comme étant le pH de la solution aqueuse dans laquelle le solide existe sous un potentiel électrique neutre. Si le pH de la solution est basique, la surface est acide, et inversement. La différence entre le PZC et l'IEPS est basée sur le phénomène d'adsorption spécifique. On peut considérer que si la grandeur mesurée ne dépend pas de la solution utilisée pour la mesurer (pH, concentration, nature des ions), alors on a affaire à un PZC. Dans le cas contraire, c'est un IEPS que l'on mesure. Par exemple, quand la mesure de goutte sessile à deux liquides est utilisée, on considère en général qu'il n'y a pas adsorption des ions de cette goutte et que la goutte déplace complètement l'alcane qui sert de deuxième liquide: on est alors en présence d’un PZC. Au contraire, dans les mesures de potentiel d'écoulement (streaming potential), la solution joue un rôle important et c'est un IEPS que l'on mesure. Enfin, la charge nette se définit grâce au pH de la solution aqueuse dans laquelle la surface métallique existe, dans un état électriquement neutre (c’est-à -dire [M-OH2+ surf]=[M-O- surf]) et au PZC.
- Si pH < PZC alors la charge nette est positive
- Si pH > PZC alors la charge nette est négative.
Il existe plusieurs méthodes expérimentales permettant de décrire l’état acido-basique de la surface : la mesure du potentiel d’écoulement, la photoélectrochimie, la mesure de l’angle de contact, et la spectroscopie XPS.
Réticulation (polymérisation)
Stabilité hydrothermale
ThermogravimétrieIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : To manage the environmental impacts of chrome tannage, a burgeoning option lies in seeking alternatives that reproduce the high hydrothermal stability and retain the versatility of chromium salts. In this study, a novel chromium-free tanning process based on in-situ condensate melamine-formaldehyde oligomer was reported. Instead of using prepared melamine-formaldehyde syntan, which inevitably contained post-condensates with compromised penetration capability and reactivity, melamine and formaldehyde monomers were first allowed to penetrate evenly into bated hides and then condensation was triggered in-situ. Total organic carbon (TOC), total nitrogen (TN), Fourier transform infrared (FTIR), and isoelectric point (IP) analysis demonstrated these in-situ condensate oligomers covalently reacted with amino or hydroxyl residues, introducing rigid and stable chemical crosslink between collagen chains. Consequently, the hydrothermal stability of the tanned leather was significantly enhanced, evidenced by thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC) and a shrinking temperature (Ts) approaching 93°C. In addition, scanning electron microscope (SEM) observation indicated that the in-situ tanned leather exhibited smoother grain, more even and much looser fiber structure compared with control, which was tanned by traditional melamine-formaldehyde syntan. According to these results, the in-situ condensation strategy developed in this study could be employed as an efficient chromium-free tannage, which eliminated the adverse effects of post-condensates in traditional melamine-formaldehyde syntan while exhibiting improved tanning efficiency. Note de contenu : - EXPERIMENTAL PROCEDURES : Materials - Preparation of modified gelatin - TOC and TN measurements - FTIR analysis - IP measurements - TGA analysis - Tanning of bated goat hides - The hydrothermal stability - Scanning Electron Microscope (SEM) observation
- RESULTS AND DISCUSSION : Tanning mechanism - Hydrothermal stability - Morphologies of fibers in the tanned leatherEn ligne : https://drive.google.com/file/d/15ZHAPD8Iu0e-UnTmXSZXuPEWRsw24vZu/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=19685
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CVIII, N° 11 (11/2013) . - p. 404-410[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15707 - Périodique Bibliothèque principale Documentaires Disponible Novel concept for low temperature curing powder coatings based on hyperbranched polyesters / Mats Johansson in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 906 (07/2000)
[article]
Titre : Novel concept for low temperature curing powder coatings based on hyperbranched polyesters Type de document : texte imprimé Auteurs : Mats Johansson, Auteur ; Eva Malmström, Auteur ; Andreas Jansson, Auteur ; Anders Hult, Auteur Année de publication : 2000 Article en page(s) : p. 49-54 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Basses températures
Copolymères greffés
Peinture poudre -- Séchage sous rayonnement ultraviolet
Polyesters
Polymères aliphatiques
Polymères cristallins
Polymères ramifiés
Réticulation (polymérisation)
Revêtements poudre:Peinture poudreIndex. décimale : 667.9 Revêtements et enduits Résumé : The concept of using hyperbranched polymers as scaffolds for solid thermoset resin applications is described. A series of semi-crystalline methacrylate-functional aliphatic polyesters has been synthesized and characterized for applications as solid thermoset resin, e.g., powder coating resins. The polyester resins have been crosslinked by UV irradiation producing either amorphous or semi-crystalline crosslinked films depending on the initial structure. The resins are based on hyperbranched aliphatic polyesters onto which crystalline linear aliphatic polyester chains have been grafted and end-capped with methacrylate moieties. The resins exhibit a rheological behavior suitable for low temperature curing powder coatings, i.e., films that can be readily formed and UV cured at temperatures below 80°C. Note de contenu : - SYNTHESIS : General procedure for grafting of poly(epsilon-caprolactone) (epsilon-PCL) polyesters 1 and 2 exemplified by synthesis of P2G-epsilonPCL(DP=10),3 - General procedure for methacrylation of the hydroxy-functional polymers 3-6 exemplified by the synthesis P2G-epsilonPCL(DP=10)-MA - UV curing (crosslinking) of polyesters 7-10:
- CHARACTERIZATION TECHNIQUES : Rheology - Thermal characterization - Residual unsaturation - Microscopy - Photo DSC - Dynamic mechanical properties
- SYNTHESIS : Graphting of epsilon-caprolactone onto the hyperbranched polyesters - Methacrylate functionalization - Rheological and physical properties of polyesters 7-10 before crosslinking - Curing performance of resins 7-10 - Mechanical propertier of UV-cured films of resins 7-10Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17985
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 72, N° 906 (07/2000) . - p. 49-54[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 001211 - Périodique Bibliothèque principale Documentaires Disponible
[article]
Titre : Novel curing : An emerging technology may allow adhesives in opaque substrates to be cured by UV or visible light Type de document : texte imprimé Auteurs : dave Bunn, Auteur Année de publication : 2012 Article en page(s) : p. 37-38 Langues : Américain (ame) Catégories : Colles:Adhésifs
Lumière visible
Luminescence
Particules (matières)
Rayonnement ultraviolet
Réticulation (polymérisation)Tags : Adhésifs Réticulation 'Lumière visible' 'Rayonnement ultraviolet' 'Matériaux opaques' 'Générateur lumière activé rayon X' 'Particules luminescentes' 'modulateur énergie' Index. décimale : 668.3 Adhésifs et produits semblables Résumé : Adhesives and coatings cured by ultraviolet (UV) or visible light have become valuable tools in modern-day assembly operations, particularly in high-technology industries such as electronics and medical devices. Most UV adhesives are based on free radical polymerization systems with acrylate or methacrylate monomers, although other systems such as cationically cured cycloaliphatic epoxies, vinyl ethers, and oxetanes are known.
- UV systems offer users the following advantages:
- Quick cure speed (often in seconds) leads to increased productivity
- Energy savings; requires a fraction of the power consumption of heat curing
- Fewer stresses and movement than in heat cure
- Less floor space due to small, compact curing systems
- Single component (no application of primers or mixing)
- Reduced work in process (assembly to pack measured in minutes)
- Safety (no hazardous solvents or other emissions)En ligne : http://www.adhesivesmag.com/articles/print/91089-novel-curing Format de la ressource électronique : Web Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=19029
in ADHESIVES & SEALANTS INDUSTRY (ASI) > Vol. 19, N° 6 (06/2012) . - p. 37-38[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13948 - Périodique Bibliothèque principale Documentaires Disponible Novel metal-free catalysts for epoxy carboxy coatings / Ravi Ravichandran in COATINGS TECH, Vol. 16, N° 3 (03/2019)
[article]
Titre : Novel metal-free catalysts for epoxy carboxy coatings Type de document : texte imprimé Auteurs : Ravi Ravichandran, Auteur ; Michael Emmet, Auteur ; Matthew Gadman, Auteur ; John Florio, Auteur ; Steven Woltornist, Auteur Année de publication : 2019 Article en page(s) : p. 28-40 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Automobiles -- Vernis
Catalyseurs
Essais accélérés (technologie)
Essais de résilience
Essais dynamiques
Formulation (Génie chimique)
Polyacryliques
Réticulation (polymérisation)
vernis en phase solvant
ViscositéIndex. décimale : 667.9 Revêtements et enduits Résumé : A new class of metal-free catalysts has been developed that promotes the crosslinking reaction of epoxy functional polymers with carboxyl functional compounds and polymers. Particularly effective at much lower cure temperatures, these catalysts provide stable single package formulations and improved resistance properties. In addition, unlike amine-based cmpounds, these catalysts do not yellow during cure or on over-bake. Note de contenu : - INTRODUCTION : Epoxy acid automotive clearcoats - Epoxy acid-based powder coatings - Binder, crosslinking chemistry, and catalysis
- EXPERIMENTAL : Experiment I : catalyst studies on NACURE XC-324 in a 1K SP epoxy/carboxy clearcoat (Materials and preparation of 1K SB epoxy/carboxy clearcoat formulation - Film preparation of 1K SB epoxy/carboxy clearcoats - Film properties of catalyzed clearcoats - Viscosity stability of epoxy carboxy liqiud coatings - Gel fraction studies - QUV resistance of catalyzed epoxy carboxy coatings - Humidity exposures of catalyzed epoxy carboxy coatings - Crickmeter abrasion - Overbake resistance) - Experiment II : Catalyst studies on NACURE XC-355 in a 2K SB epoxy/carboxy clearcoat (materials and preparation of 2K SB/epoxy carboxy clearcoat formulation - Film preparation of 2KSB epoxy/carboxy clearcoat - Film preparation of HMMM crosslinked acrylic and epoxy/carboxy clearcoats - Cure response of acrylic OH/HMMM and acrylic COOH/GMA - Environmental etch comparison of acrylic OH/HMMM vs acrylic COOH/GMA
- Fig. 1 : Epoxy carboxy crosslinking reaction
- Fig. 1a : Viscosity stability of epoxy/carboxy SB coatings (60°C storage)
- Fig. 1b : Viscosity stability of epoxy/carboxy SB coatings (50°C storage)
- Fig. 1c : Viscosity stability of epoxy/carboxy SB coatings (ambient storage)
- Fig. 2 : Percent weight retention after 6h of reflux with acetone/metanol (1/1)
- Fig. 3 : Yellowness measurements after QUV exposure
- Fig. 4 : Change in gloss following crockmeter abrasion
- Fig. 5 : Yellowing (b*) and total color (E*) change of clearcoats after overbake
- Fig. 6 : Oscillation curve of complet viscosity and temperature as a function of time
- Fig. 7 : MEK resistance of hardness of epoxy/acid clearcoats-100°C/30 min bake
- Table 1 : Classes of available catalyst technologies
- Table 2 : 1K SB epoxy/carboxy clearcoat
- Table 3a : Film properties of carboxy functional acrylic and GMA epoxy-120°C/30 min
- Table 3b : Film properties of carboxyl functional acrylic and GMA epoxy - 110°C/30 min
- Table 4 : Viscosity stability of epoxy carboxy liquid coatings (60°C/16 h)
- Table 5 : Gel fraction studies after 6h Soxhlet extraction with acetone/methanol (1/1)
- Table 6 : Yellowness measurements after QUV exposure-b*values
- Table 7 : Yellowness measurements after QUV exposure-Δ*values
- Table 8 : Humidity exposures of catalyzed epoxy/carboxy coatings-Blister ratings
- Table 9 : Visual rating for crockmeter tests-0-R rating
- Table 10 : Images with visual rating and change in gloss following crockmeter abrasion
- Table 11 : Change in color values of catalyzed clearcoats after overbake
- Table 12 : 2K solventborne epoxy/carboxy clearcoat
- Table 13a : Pre-experiment steps for oscillation tests
- Table 13b : Protocol for oscillation tests
- Table 14 : Film properties of carboxyl functional acrylic and GMA epoxy-100°C/30 min
- Table 15 : Yellowing resistance follwing 100°C/30 min overbake
- Table 16 : Total color change following 100°C/30 min overbake
- Table 17 : (a) Hydroxyl functional acrylic/HMMM vs (b) acid functional acrylic/GMA epoxy
- Table 18 : MEK resistance of (a) acrylic OH/HMMM vs (b) acrylic COOH/GMA
- Table 19 : Acid etch resistance of (a) acrylic OH/HMMM vs (b) acrylic COOH/GMAEn ligne : https://drive.google.com/file/d/1hbklMv6qE5mymZKYqIQ2MXKYVZtkH1VA/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=32045
in COATINGS TECH > Vol. 16, N° 3 (03/2019) . - p. 28-40[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 20698 - Périodique Bibliothèque principale Documentaires Disponible A novel process for making patent leather / F. Scholnick in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXIV (Année 1989)
[article]
Titre : A novel process for making patent leather Type de document : texte imprimé Auteurs : F. Scholnick, Auteur ; Peter R. Buechler, Auteur Année de publication : 1989 Article en page(s) : p. 65-70 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Brillance (optique)
Copolymère uréthane acrylique
Cuirs et peaux -- Finition
Formulation (Génie chimique)
Résistance à l'abrasion
Réticulation (polymérisation)
Souplesse (mécanique)
Traction (mécanique)
VernisIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Radiation curable formulations have been developed for use in preparation of finishes suitable for patent leather. Curing can be achieved by either ultraviolet or electron beam irradiation. In contrast to conventional methods, complete finish application is obtained rapidly, without the use of heating ovens, and with no air pollution. Patent leather produced by this process exhibits good gloss and flexibility and excellent abrasion resistance. Flexibility was affected by the type and amount of crosslinking agent incorporated into the coating as well as by the acrylated urethane oligomer used as the coating backbone. The effects of varying the formulation on final finish properties are discussed. Note de contenu : - TABLE I : Variation of gloss with coating thickness
- TABLE II : Variation of flexibility with systems (one 4-mil coat)
- TABLE III : Variation of flexibility with coating systems (two 4 mil coats)
- TABLE IV : Tensile strength and elongation at failure of various formulations
- TABLE V : Patent leather properties from uvithane 892 formulation
- TABLE V : Patent leather properties from uvithane 892 formuationEn ligne : https://drive.google.com/file/d/16OZQuhEJFcHYADGdxXSc7JKZAidFYHQu/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17288
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXXIV (Année 1989) . - p. 65-70[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 008089 - Périodique Bibliothèque principale Documentaires Disponible Novel radiation curable polyurethane dispersions in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 199, N° 4538 (07/2009)
PermalinkNovel solutions for wood coatings / Adri van der Waals in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 199, N° 4532 (01/2009)
PermalinkNovel versatile oligomer for thermallly, UV-, and ambient curable organic-inorganic hybrid coatings / Tahereh Hayeri in COATINGS TECH, Vol. 20, N° 5 (09-10/2023)
PermalinkNubuck finishing with water-based carbonyl-functional polymers / Lluis Ollé in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 92, N° 5 (09-10/2008)
PermalinkOligourethane diol/melamine high solids / M. Yaseen in EUROPEAN COATINGS JOURNAL (ECJ), N° 5/97 (05/1997)
PermalinkOn the synthesis and characterization of new low temperature curing powder coatings cured with radiation / Mats Johansson in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 884 (09/1998)
PermalinkOptimisation de la cuisson des pièces en élastomère / M. Pompéi in CAOUTCHOUCS & PLASTIQUES, N° 748 (03/1996)
PermalinkOutlook for zero-VOC resins / Frank N. Jones in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 73, N° 916 (05/2001)
PermalinkOxidative crosslinking of alkyd resins studied with mass spectrometry and NMR using model compounds / W. J. Muizebelt in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 70, N° 876 (01/1998)
PermalinkParallel measurements and engineering simulations of conversion, shear modulus, and internal stress during ambient curing of a two-component epoxy coating / Qiong Li in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 19, N° 5 (09/2022)
PermalinkPartnering Michael addition with powder coating / Pengcheng Yang in EUROPEAN COATINGS JOURNAL (ECJ), (12/2023)
PermalinkPermalinkLes peintures aqueuses à haute performance / Association Française des Techniciens des Peintures, Vernis, Encres et Adhésifs / Paris : AFTPVA (1996)
PermalinkPerformance of bismuth vanadates in polyester/trimellictic acid triglycidylester powder in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 203, N° 4581 (02/2013)
PermalinkPerformance optimization of 100% solids, UV-cure inks and wood fillers using aluminum trihydroxide (ATH) filler / N. R. Dando in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 68, N° 859 (08/1996)
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