| 1. |
- Claesson, PM, et al.
(författare)
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Functionalized mica surfaces obtained by a cold plasma process
- 1990
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Ingår i: Progress in Colloid and Polymer Science. - 0340-255X .- 1437-8027. ; 82, s. 330-336
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Tidskriftsartikel (refereegranskat)abstract
- A surface modification procedure based on the cold plasma technique has been utilized in order to introduce new functional groups onto muscovite mica surfaces. In the first reaction step mica surfaces are exposed to a water vapor plasma. The interaction between mica surfaces and reactive species in the plasma results in information of surface hydroxyl groups. These groups are reactive toward chlorosilanes in the gas phase, which provides a versatile way to obtain mica surfaces with a variety of different surface chemical groups. For instance, poly(ethylene oxide) chains have been covalently attached to mica surfaces.-In a different surface modification route, mica surfaces have been coated with thin plasma polymer layers. Mechanical and surface properties of plasma polymer films depend, of course, on the type of monomer, but also on the condition used during polymerization (e.g., flow rate, pressure and discharge power). The surface force technique has, together with spectroscopic analyses, provided information about how the adhesion force and mechanical strength of different plasma polymers of acrylic acid depend on the polymer structure.
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| 2. |
- Kiss, E, et al.
(författare)
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Chemical derivatization of muscovite mica surfaces
- 1990
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Ingår i: Colloids and Surfaces. - 0166-6622 .- 1873-4340. ; 49, s. 335-342
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Tidskriftsartikel (refereegranskat)abstract
- A method to modify mica chemically by means of a plasma discharge in water vapour, to form reactive silanol groups, followed by silyation with isocyanatopropyldimethylchlorosilane has been developed. The introduction of isocyanatopropyl moieties on the surface enables the performance of a wide range of organic derivatization reactions. As examples, amino- and ethylene oxide-functional surfaces have been prepared. The surface film compositions have been quantitatively studied by ESCA. The interaction force in water between poly (ethylene oxide) layers covalently attached to mica, as measured in a surface force apparatus, was repulsive at separations less than 20-30 nm.
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| 3. |
- Kiss, E, et al.
(författare)
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Static and dynamic wetting behaviour of poly(ethylene oxide) layer formed on mica substrate
- 1991
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Ingår i: Colloids and Surfaces. - 0166-6622 .- 1873-4340. ; 58, s. 263-270
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Tidskriftsartikel (refereegranskat)abstract
- Dynamic wetting of poly(ethylene oxide)-, PEO; grafted mica surface has been investigated by a tensiometric method based on the Wilhelmy balance. Advancing and receding contact angles were determined under static conditions as well as at different contact line velocities in the range 0.1-5.0 mm s-1. The wetting medium and conditions were chosen according to the phase behaviour of PEO determined in solution. Wetting parameters characterizing the surface/liquid interaction measured on a system below and above the theta conditions differ considerably. Contact angles of water or aqueous electrolyte solution were found to be increased while heterogeneity of the surface was reduced with increasing temperature and salt concentration stressing the role of chain mobility in the special properties of PEO surface. Dynamic wetting of poly(ethylene oxide)-, PEO; grafted mica surface has been investigated by a tensiometric method based on the Wilhelmy balance. Advancing and receding contact angles were determined under static conditions as well as at different contact line velocities in the range 0.1-5.0 mm s-1. The wetting medium and conditions were chosen according to the phase behaviour of PEO determined in solution. Wetting parameters characterizing the surface/liquid interaction measured on a system below and above the theta conditions differ considerably. Contact angles of water or aqueous electrolyte solution were found to be increased while heterogeneity of the surface was reduced with increasing temperature and salt concentration stressing the role of chain mobility in the special properties of PEO surface.
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