ISSN:
1435-1536
Keywords:
Surface modification
;
heats of immersion
;
silane-treated silica
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The surface of silica was treated with trimethylchlorosilane (TMCS) and hexa-methyldisilazane (HMDS) respectively and the immersional heat into water, adsorption capacity for water vapor and infrared absorption spectra were measured. TMCS reacts with freely vibrating silanols while HMDS also reacts with other silanols. By treatment with silane, the silica surface is covered by the trimethylsilyl group, a maximum amount of which attains 1 meq/g (3 groups/nm2). As the amount of the trimethylsilyl group on silica increases, the immersional heat of silica into water decreases and attains a constant value of about 25 erg/cm2, which is the typcial value for a hydrophobic surface. The interaction of the trimethylsilyl group with water is weak, therefore the adsorptive capacity for water vapor is lessened remarkably by treatment with silane.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01458342
