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Synthesis and tribological properties of S- and P-free borate esters with different chain lengths / Guangbin Yang in Transactions of the ASME . Journal of tribology, Vol. 133 N° 2 (Avril 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 133 N° 2 (Avril 2011) . - 07 p. Titre : Synthesis and tribological properties of S- and P-free borate esters with different chain lengths Type de document : texte imprimé Auteurs : Guangbin Yang, Auteur ; Zhanming Zhang, Auteur ; Guihui Li, Auteur Année de publication : 2012 Article en page(s) : 07 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Chemical  structure  Fourier  transform  spectra  Friction  Hydrogen  bonds  Infrared  spectra  Lubricating  oils  Lubrication  Materials  preparation  Organic  compounds  Scanning  electron  microscopy  Steel  Surface  morphology  Thermal  analysis  Thermal  stability  Wear  Wear  resistance  Wear  testing  X-ray  photoelectron  spectra Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Three kinds of S- and P-free borate esters containing N with different alkyl chain lengths were prepared by using boric acid, ethanolamine, and alkyl-alcohol as the starting materials. The chemical structure of the products was analyzed by means of Fourier transformation infrared spectrometry, elemental analysis, and so on. The thermal stability of the products was evaluated by thermogravimetric analysis. The tribological properties of the synthesized borate esters as lubricating oil additives in liquid paraffin were evaluated using a four-ball friction and wear tester while the morphologies of the worn scars of the steel balls were observed using a scanning electron microscope. The chemical components on the worn surfaces of the steel balls were analyzed using an X-ray photoelectron spectroscopy. Results show that all the three kinds of synthetic borate esters as additives in liquid paraffin possess good antiwear performance and may be used as promising S- and P-free environmentally acceptable lubricating oil additives. Particularly, borate ester with short alkyl chain length at a low concentration in liquid paraffin was more effective in reducing wear, and the antiwear ability of the additives decreased with increasing alkyl chain length. The antiwear ability of the N-containing borate esters as additives in liquid paraffin might be closely related to the formation of hydrogen bonds via N with a high electronegativity and small atomic radius and the easy permeation of electron-deficient B on the rubbing steel surfaces. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...] [article] Synthesis and tribological properties of S- and P-free borate esters with different chain lengths [texte imprimé] / Guangbin Yang, Auteur ; Zhanming Zhang, Auteur ; Guihui Li, Auteur . - 2012 . - 07 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 133 N° 2 (Avril 2011) . - 07 p. Mots-clés : Chemical  structure  Fourier  transform  spectra  Friction  Hydrogen  bonds  Infrared  spectra  Lubricating  oils  Lubrication  Materials  preparation  Organic  compounds  Scanning  electron  microscopy  Steel  Surface  morphology  Thermal  analysis  Thermal  stability  Wear  Wear  resistance  Wear  testing  X-ray  photoelectron  spectra Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Three kinds of S- and P-free borate esters containing N with different alkyl chain lengths were prepared by using boric acid, ethanolamine, and alkyl-alcohol as the starting materials. The chemical structure of the products was analyzed by means of Fourier transformation infrared spectrometry, elemental analysis, and so on. The thermal stability of the products was evaluated by thermogravimetric analysis. The tribological properties of the synthesized borate esters as lubricating oil additives in liquid paraffin were evaluated using a four-ball friction and wear tester while the morphologies of the worn scars of the steel balls were observed using a scanning electron microscope. The chemical components on the worn surfaces of the steel balls were analyzed using an X-ray photoelectron spectroscopy. Results show that all the three kinds of synthetic borate esters as additives in liquid paraffin possess good antiwear performance and may be used as promising S- and P-free environmentally acceptable lubricating oil additives. Particularly, borate ester with short alkyl chain length at a low concentration in liquid paraffin was more effective in reducing wear, and the antiwear ability of the additives decreased with increasing alkyl chain length. The antiwear ability of the N-containing borate esters as additives in liquid paraffin might be closely related to the formation of hydrogen bonds via N with a high electronegativity and small atomic radius and the easy permeation of electron-deficient B on the rubbing steel surfaces. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...]