[article]
Titre : |
Methylcyclohexyl diamine (Baxxodur® EC 210) : A hardener for epoxy systems with superior carbamate stability |
Type de document : |
texte imprimé |
Auteurs : |
Irene Gorman, Auteur ; Michael Henningsen, Auteur ; Frank Hettche, Auteur ; Matthaeus Kopczynski, Auteur ; Alexander Panchenko, Auteur ; Marc Hofmann, Auteur ; Chin Li, Auteur ; Raj Sundar, Auteur |
Année de publication : |
2018 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Calorimétrie Epoxydes Méthylcyclohexyl diamine Réticulants Revêtements -- Additifs Revêtements -- Propriétés mécaniques Revêtements -- Propriétés thermiques Revêtements organiques Rhéologie
|
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
Epoxy-based industrial maintenance coatings offer excellent chemical and mechanical performance. However, the amine type hardeners often employed can easily react with atmospheric carbon dioxide and moisture to form carbamate salts. These carbamate salts accumulate on the surface and cause blush and intercoat adhesion issues. Adducts based on methylcyclohexyl diamine (MCDA, Baxxodur® EC 210), a cycloaliphatic diamine curative for epoxy resin systems, displayed enhanced carbamate stability compared to adducts based on both isophorone diamine (IPDA) and m-xylylene diamine (MXDA). This behaviour was further validated in coating tests, where coating formulations based on MCDA exhibited superior gloss. The cure behavior, mechanical properties, and thermal properties of MCDA, IPDA, and MXDA cured systems were also assessed using various analytical techniques such as differential scanning calorimetry and rheology. Overall, MCDA was proven to be an attractive building block for epoxy diamine, industrial coating systems. |
Note de contenu : |
- EXPERIMENTAL : Materials - Adduct synthesis - Preparation of reactive DEGBA-adduct - Mixtures - Methods
- RESULTS AND DISCUSSION : Adduct production - Thermal properties - Rheological properties - Shore D development - Carbamate stability
- Fig. 1 : Diamine-type epoxy hardeners employed in this study
- Fig. 2 : Idealized MCDA-based adduct
- Fig. 3 : Viscosity development of DGEBA hardened with the various adducts and adduct-BnOH mixtures, at a) 23 °C and b) 75 °C. Viscosity data for DGEBA hardened with IPDA-A8 is not reported because the starting viscosity of this formulation exceeded 10,000 mPas
- Fig. 4 : Shore D development over time of DGEBA hardened with MCDA-A16, IPDA A16, and MXDA-A16 adducts at 23 °C (ambient atmosphere)
- Fig. 5 : Adducts and adduct-BnOH mixtures aged at 23 °C and 50% relative humidity for 48 hours. The presence of carbamates was detected visually through the observation of white precipitate or surface irregularities, as was the case for IPDA-A2.5-BnOH
- Fig. 6 : Carbamate stability of pure adducts and adduct-BnOH mixtures aged at 23 °C and 50% relative humidity, and spectral gloss readings of DGEBA hardened with A2.5-BnOH adducts at 8 °C and 70% relative humidity
- Table 1 : Summary of adducts and adduct-BnOH mixtures
- Table 2 : Thermal properties of DGEBA hardened with adducts and adduct-BnOH mixtures
- Table 3 : Rheological properties of DGEBA hardened with adducts and adduct-BnOH mixtures
- Table 4 : Shore D and tack development of DGEBA hardened with adducts and adduct-BnOH mixtures |
En ligne : |
https://www.coatingsworld.com/issues/2018-05-01/view_features/methylcyclohexyl-d [...] |
Format de la ressource électronique : |
Html |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=32520 |
in COATINGS WORLD > Vol. 23, N° 5 (05/2018)
[article]
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