[article]
Titre : |
Lubricating and waxy esters II : Synthesis, crystallization, and melt behavior of branched monoesters |
Type de document : |
texte imprimé |
Auteurs : |
Laziz Bouzidi, Auteur ; Shaojun Li, Auteur ; Steve Di Biase, Auteur |
Année de publication : |
2013 |
Article en page(s) : |
pp. 14892-14902 |
Note générale : |
Industrial chemistry |
Langues : |
Anglais (eng) |
Mots-clés : |
Crystallization |
Résumé : |
A comprehensive study of branched derivatives of four pure jojoba wax-like esters (JLEs), having 36, 40 (two isomers), and 44 carbons was conducted to elucidate their crystallization and melting behavior. Crystallization and melting characteristics depended strongly on the number of branches, molar mass, and symmetry. The derivatives demonstrated a very strong tendency to form glassy liquids rather than crystal phases and remain liquid-like at very low temperatures. As the number of branches increased, their crystallinity decreased drastically while their glassy phase increased concomitantly with the depression of the onset of crystallization and/or glass transition temperature. A variety of possible transformation paths, ranging from very little polymorphic activity to extremely polymorphic behavior, depending on number of branches, mass, and symmetry were revealed. It is shown that asymmetry plays a large role in the low temperature behavior, rendering the branched derivatives of the asymmetrical JLEs much better candidates for lubricant formulations. |
ISSN : |
0888-5885 |
En ligne : |
http://cat.inist.fr/?aModele=afficheN&cpsidt=26620402 |
in Industrial & engineering chemistry research > Vol. 51 N° 45 (Novembre 2012) . - pp. 14892-14902
[article] Lubricating and waxy esters II : Synthesis, crystallization, and melt behavior of branched monoesters [texte imprimé] / Laziz Bouzidi, Auteur ; Shaojun Li, Auteur ; Steve Di Biase, Auteur . - 2013 . - pp. 14892-14902. Industrial chemistry Langues : Anglais ( eng) in Industrial & engineering chemistry research > Vol. 51 N° 45 (Novembre 2012) . - pp. 14892-14902
Mots-clés : |
Crystallization |
Résumé : |
A comprehensive study of branched derivatives of four pure jojoba wax-like esters (JLEs), having 36, 40 (two isomers), and 44 carbons was conducted to elucidate their crystallization and melting behavior. Crystallization and melting characteristics depended strongly on the number of branches, molar mass, and symmetry. The derivatives demonstrated a very strong tendency to form glassy liquids rather than crystal phases and remain liquid-like at very low temperatures. As the number of branches increased, their crystallinity decreased drastically while their glassy phase increased concomitantly with the depression of the onset of crystallization and/or glass transition temperature. A variety of possible transformation paths, ranging from very little polymorphic activity to extremely polymorphic behavior, depending on number of branches, mass, and symmetry were revealed. It is shown that asymmetry plays a large role in the low temperature behavior, rendering the branched derivatives of the asymmetrical JLEs much better candidates for lubricant formulations. |
ISSN : |
0888-5885 |
En ligne : |
http://cat.inist.fr/?aModele=afficheN&cpsidt=26620402 |
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