Intermolecular Alignment Dependence of Ethylene Glycol Flow on the Chemical Nature of the Solid Surface (Borosilicate and SnO2)

• Main Authors: Quintella Cristina M., Gonçalves Cristiane C., Pepe Iuri, Lima Ângelo M. V., Musse Ana P. S.
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Química 2001-01-01
• Series: Journal of the Brazilian Chemical Society
• Subjects: liquid-solid interface; fluorescence depolarization; anisotropy; liquid flow; dynamic surface tension
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532001000600015
• ISSN: 0103-5053

This work studied ethylene glycol (MEG) flowing on two different solid surfaces, borosilicate and thin dioxide (SnO2). Intermolecular alignment, determined as polarization and anisotropy, showed dependence on the solid chemical nature. The ratio between dynamic surface tensions was found 1.09 ± 0.07, being stronger for MEG/borosilicate than for MEG/SnO2. The capillary ratio found was 0.92 ± 0.06, being smaller for MEG/borosilicate. Static contact angle measurements gave lower values for borosilicate than for SnO2. Both polarization and anisotropy maps presented higher values for MEG/SnO2, which can be explained by MEG/borosilicate higher interfacial interaction. The results obtained are compatible with stronger bulk phenomena for MEG/SnO2 and with stronger interfacial phenomena for MEG/borosilicate. This may be due to borosilicate being more electronegative, yielding more efficiently hydrogen bonds with MEG.