Titre : |
Melamine ethoxylates as novel formaldehyde free replacements of resin re-tanning agents |
Type de document : |
texte imprimé |
Auteurs : |
Jochen Ammenn, Auteur |
Année de publication : |
2022 |
Article en page(s) : |
p. 296-301 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Agents de tannage Cuirs et peaux de bovins Ethoxylates de mélamine Formaldéhyde -- Suppression ou remplacement Produits de condensation (chimie) Retannage Tannage synthétique Wet-blue (tannage)Peau tannée au chrome (le chrome donne une couleur bleue)
|
Index. décimale : |
675.2 Préparation du cuir naturel. Tannage |
Résumé : |
Melamine urea formaldehyde condensates or resin re-tanning agents are commonly used in the leather industry. They give rise to homogeneous filling, are easily and widely applicable, but generally contribute to free formaldehyde, measurable in emission or extraction methods. Many projects to resolve this issue have been carried out. The weakness of the resin re-tanning is the reversibility of the bond formation between formaldehyde and two amino groups. The formaldehyde forms a methylene group after condensation with two amino groups and releases water. This methylene group can be hydrolyzed under acidic conditions to release formaldehyde again, reversing the synthesis.
Melamine ethoxylates were found to be a formaldehyde free, stable, and easily applicable alternative. Besides the fact that they are made without formaldehyde, it proved to be possible to incorporate renewable components into their synthesis, giving rise to an even more sustainable product. Another sustainable aspect of this chemistry is the delivery of the potential product as a concentrated liquid versus most resin re-tanning agents being placed into the market as spray dried powders, consuming significant amounts of energy in the process.
Melamine ethoxylates show advantages in application on leather in comparison with classical resin re-tanning agents. An insight into the scope of application will be given, showing that melamine ethoxylates can be considered a formaldehyde free replacement for resin re-tanning agents. |
Note de contenu : |
- Melamine urea formaldehyde condensates
- Melamine ethoxylates
- Table 1 : Screening results of the re-tanning of bovine wet blue of different melamine ethoxylates against a standard melamine urea formaldehyde condensate and polyethylene glycol : + = better ; 0 = similar ; — = worse
- Table 2 : Re-tanning of bovine wet blue with the optimized melamine ethoxylate against a standard melamine urea formaldehyde condensate : + = better; 0 = similar ; - = worse
- Table 3 : Results of re-tanning of bovine wet blue or wet white with melamine ethoxylates in a mixed recipe compared to a melamine urea formaldehyde condensate in the mixed recipe : + = better; 0 = similar; - = worse |
En ligne : |
https://drive.google.com/file/d/1cuWtS0wR-6zJregVnQ4eK0FqHZOfhLNC/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37822 |
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXVII, N° 7 (07/2022) . - p. 296-301