Cure and morphology of epoxy/polyester powder coatings containing titanium dioxide : a thermally stimulated discharge study / Emile C. Trottier in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 9, N° 6 (11/2012)  

[article]  inJOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 9, N° 6 (11/2012) . - p. 717-724 Titre : Cure and morphology of epoxy/polyester powder coatings containing titanium dioxide : a thermally stimulated discharge study Type de document : texte imprimé Auteurs : Emile C. Trottier, Auteur ; Stanley Affrossman, Auteur ; Richard A. Pethrick, Auteur Année de publication : 2012 Article en page(s) : p. 717-724 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Dioxyde de titane Epoxydes Mesures diélectriques Polyesters Réticulation (polymérisation) Revêtements poudre:Peinture poudre Stimulation électrique Index. décimale : 667.9 Revêtements et enduits Résumé : This article describes the use of thermally stimulated electrical discharge (TSD) measurements in the study of the cure processes occurring for a range of titanium dioxide, silica, and zinc oxide-pigmented epoxy polyester films. The unfilled polyester–epoxy resin system exhibits a simple TSD profile indicative of a combination of space charge and dipole relaxation processes. The addition of the Modaflow, which is used to aid in the dispersion of the pigment in the system, induces phase separation under certain cure conditions. In a number of systems, two lower temperature Tg peaks were initially observed, which collapsed into a single peak on post cure. The principal difference between the two grades of titanium dioxide was the size of the space charge peak, which is a direct indication of the mobile ion content in the material. The sulfate has higher mobile ion content than the chloride route material. Differences were observed between traces of silica and zinc oxide, which reflect the ability of the particles to interact with the resin and form a dense matrix. Silica at low concentrations is able to reduce the space charge peak which implies it can trap ions. The TSD study indicates that the pigments are able to change the morphology of the matrix which is being formed. Note de contenu : - EXPERIMENTAL : Resins - Pigments - Thermally stimulated discharge measurements - RESULTS AND DISCUSSION : Studies of the base resin system cured at 413K - Studies of the base resin system with Modaflow cured at various temperatures - Titanium dioxide pigments A and B - Silica and zinc oxide effects - ACTIVATION ENERGY CALCULATIONS DOI : 10.1007/s11998-012-9410-1 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-012-9410-1.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=16657 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
14359	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Dielectric studies of epoxy/polyester powder coatings containing titanium dioxide, silica, and zinc oxide pigments / Emile C. Trottier in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 9, N° 5 (09/2012)  

[article]  inJOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 9, N° 5 (09/2012) . - p. 525-539 Titre : Dielectric studies of epoxy/polyester powder coatings containing titanium dioxide, silica, and zinc oxide pigments Type de document : texte imprimé Auteurs : Emile C. Trottier, Auteur ; Stanley Affrossman, Auteur ; Richard A. Pethrick, Auteur Année de publication : 2012 Article en page(s) : p. 525-539 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Diélectriques Dioxyde de titane Epoxydes Oxyde de zinc Polyesters Revêtements poudre:Peinture poudre Silice La silice est la forme naturelle du dioxyde de silicium (SiO2) qui entre dans la composition de nombreux minéraux. La silice existe à l'état libre sous différentes formes cristallines ou amorphes et à l'état combiné dans les silicates, les groupes SiO2 étant alors liés à d'autres atomes (Al : Aluminium, Fe : Fer, Mg : Magnésium, Ca : Calcium, Na : Sodium, K : Potassium...). Les silicates sont les constituants principaux du manteau et de l'écorce terrestre. La silice libre est également très abondante dans la nature, sous forme de quartz, de calcédoine et de terre de diatomée. La silice représente 60,6 % de la masse de la croûte terrestre continentale. Index. décimale : 667.9 Revêtements et enduits Résumé : Dielectric measurements are reported covering a frequency range from 10?3 to 105 Hz and a temperature range from ~355 to 410 K for a pigmented epoxy/polyester resin powder coating system. A large low frequency ohmic conduction was observed in all these systems and the electrical modulus representation was used to aid analysis. A space charge relaxation indicative of heterogeneity in the matrix was observed in the pure resin and the pigmented coatings. In the pure resin, the heterogeneity is associated with nanoscale phase separation. A study with the resin modified with Modaflow, an ester copolymer dispersion agent, shows that the dipole relaxation is more ideal and the activation energy for dipole relaxation is reduced compared with that observed in the pure resin. The introduction of titanium dioxide pigment reduces the activation energy but also increases the magnitude of the ohmic conductivity and space charge contributions to the dielectric permittivity. All the systems exhibit heterogeneity and in the case of a pigmented system charge carriers can be introduced into the system by the pigment. Clear differences are observed between TiO2 produced via the chloride and sulfate routes, reflecting different levels of charge carriers and ion mobile in the resin system. High levels of mobile ions were also observed when zinc oxide and silica were used as pigments. Note de contenu : - EXPERIMENTAL : Materials : titanium dioxide pigments - Surface area - Other pigments - Resins - Formulation of powder coating - Dielectric measurements - Dielectric theory results and discussion - RESULTS AND DISCUSSION : Unpigmented resin with modaflow - Unpigmented resin without modaflow - RESIN CONTAINING TITANIUM DIOXIDE PIGMENT : Titanium dioxide produced via the chloride route : Titanium dioxide produced via the sulfate route - Investigation of the possible influence of zinc oxide and silica on the relaxations DOI : 10.1007/s11998-012-9405-y En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-012-9405-y.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=16024 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
14190	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Effect of surface treatments of titanium dioxide pigments on the cure of polyester/triglycidyl isocyanurate powder coatings / Stanley Affrossman in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 12, N° 6 (11/2015)  

[article]  inJOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 12, N° 6 (11/2015) . - p. 1053-1064 Titre : Effect of surface treatments of titanium dioxide pigments on the cure of polyester/triglycidyl isocyanurate powder coatings Type de document : texte imprimé Auteurs : Stanley Affrossman, Auteur ; Anthony McKee, Auteur ; Richard A. Pethrick, Auteur Année de publication : 2015 Article en page(s) : p. 1053-1064 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Analyse thermomécanique dynamique Dioxyde de titane Isocyanurate de triglycidyle Pigments inorganiques Polyesters Revêtements poudre Traîtements de surface Index. décimale : 667.9 Revêtements et enduits Résumé : Titanium dioxide pigments will typically have an inorganic surface coating based on a blend of alumina and silica and an organic treatment. Both the organic and inorganic treatments can influence the cure characteristics of polyester powder coatings. This paper attempts to explore the connectivity between the nature of the coating and the cure behavior of a typical heat-cured epoxidized isocyanurate formulation. It is found that a high silica:alumina content in the inorganic pacification layer significantly retards the cure process, but is influenced by the nature of the organic treatment. The organic surface treatment may accelerate or retard the initial cure process and gelation times. Elemental analysis indicates that some of the pigments studied have a significantly higher zirconium content and exhibited enhanced cure rates compared with those with the lower zirconium content. This paper illustrates the potential effects of different grades of titanium dioxide on the cure of polyester powder coatings. Note de contenu : - EXPERIMENTAL : Materials - Titanium dioxide pigments - Surface area measurements - Powder coating production - Strathclyde curometer - Thermally stimulated discharge measurements - Dynamic mechanical thermal analysis - RESULTS AND DISCUSSION : Curometer measurements - Effects of organic surface treatment of the pigment on the cure behavior - Trimethyol propane (TMP)- Triethylamine (TEA) - Trimethyol propane (TMP)/polyethylene wax - Modaflow effects on cure - Effect of pigment loading in a Modaflow-free coating - Effect of pigment loading with 1% Modaflow being present - Effect of pigment loading with 4% Modaflow being present - Conclusion from the curometer study - Thermally stimulated discharge spectroscopy TSD - Dynamic mechanical thermal analysis DOI : 10.1007/s11998-015-9697-9 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-015-9697-9.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24957 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
17585	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Rheological studies of the cure of epoxy/powder coatings containing titanium dioxide / Emile C. Trottier in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 9, N° 6 (11/2012)  

[article]  inJOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 9, N° 6 (11/2012) . - p. 725-733 Titre : Rheological studies of the cure of epoxy/powder coatings containing titanium dioxide Type de document : texte imprimé Auteurs : Emile C. Trottier, Auteur ; Stanley Affrossman, Auteur ; Richard A. Pethrick, Auteur Année de publication : 2012 Article en page(s) : p. 725-733 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Dioxyde de titane Epoxydes Oxyde de zinc Polyesters Réticulation (polymérisation) Revêtements poudre:Peinture poudre Rhéologie Rhéomètres Silice La silice est la forme naturelle du dioxyde de silicium (SiO2) qui entre dans la composition de nombreux minéraux. La silice existe à l'état libre sous différentes formes cristallines ou amorphes et à l'état combiné dans les silicates, les groupes SiO2 étant alors liés à d'autres atomes (Al : Aluminium, Fe : Fer, Mg : Magnésium, Ca : Calcium, Na : Sodium, K : Potassium...). Les silicates sont les constituants principaux du manteau et de l'écorce terrestre. La silice libre est également très abondante dans la nature, sous forme de quartz, de calcédoine et de terre de diatomée. La silice représente 60,6 % de la masse de la croûte terrestre continentale. Index. décimale : 667.9 Revêtements et enduits Résumé : The cure characteristics of a series of powder coatings containing titanium dioxide dispersed in an epoxy/polyester matrix are reported. The titanium dioxide pigments were produced via both the chloride and sulfate routes and coated with varying amounts of alumina and silica. Comparison data for formulations containing zinc oxide and silica are also included. The time to gelation for these powder coatings depends on a number of factors. Increasing the level of flow agent significantly reduces the time to gelation. The presence of traces of zinc inhibits cure in the case of the sulfate-based pigments. Varying levels of alumina and silica in the coating on the titanium dioxide coating also influence the time to gelation. Increasing the level of silica on the chloride-based coating increases the time to gelation, whereas in the case of the sulfate based coating the time to gelation is shortened. These differences are attributed to the effects of zinc in the coating and the effectiveness of the dicyandiamide catalysts. Note de contenu : - MATERIALS : Titanium dioxide pigments - Surface area - Surface acidity - Other pigments - Resins - Formulation of powder coating - RHEOLOGICAL MEASUREMENTS : Effect of Modaflow on the cure process - Effect of TiO2 grade on the cure process - Effect of zinc oxide on the cure behavior - Effects of silica on the cure behavior - Effect of TiO2 loading on cure behavior DOI : 10.1007/s11998-012-9417-7 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-012-9417-7.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=16658 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
14359	-	Périodique	Bibliothèque principale	Documentaires	Disponible

---

1 (1 - 4 / 4)