Abstract
Long chain alcohols (1-dodecanol, 1-tetradecanol, 1-octadecanol) have been reacted at 130°C with E-glass plates, fibres and powders to modify the solid surface in order to enhance their bonding as reinforcing materials in polymer matrices. Silane-coupling agents are generally used for such modification processes but long chain alcohols may offer a cheaper alternative. Alcohols are known to bond to silica surfaces but less information is available for glass surfaces. In this investigation three techniques - contact angle, diffuse reflectance Fourier transform infrared spectroscopy (DRIFT) and X-ray photoelectron spectroscopy (XPS) - are used to study alcohol-modified glass surfaces. It is found that alcohols adhere to the glass surface even after several organic solvent (hexane or cyclohexane) extraction processes, maintaining a high advancing water contact angle of 85-97°. These contact angle values correspond to those typical for exposed methylene groups as in a polyethylene-like surface or a surface with multilayered 'islands', i.e. incomplete coverage of the glass surface. Infrared DRIFT spectra from the methylene groups give 1-5 times monolayer coverage. Despite uncertainties in the quantification method multilayers in adsorbed regions are indicated. XPS analysis shows a silica-rich surface with loss of Na, B, Fe, Mg and K from the glass and fibre surfaces during manufacture compared with bulk E-glass. Angle-resolved XPS does not suggest a highly ordered monolayer adsorption of the alcohol molecules on the glass plates but, instead, disordered multilayers. The adsorbed alcohol is apparently stable giving altered hydrophobicity, albeit without complete monolayer coverage.
Original language | English |
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Pages (from-to) | 11-22 |
Number of pages | 12 |
Journal | Colloids and Surfaces A: Physicochemical and Engineering Aspects |
Volume | 110 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1996 |
MoE publication type | A1 Journal article-refereed |
Keywords
- E-glass fibres
- adsorption
- long chain alcohols