There are two capital types of solid surfaces with which liquids can interact. Traditionally, solid surfaces accept been disconnected into high-energy debris and low-energy types. The about activity of a solid has to do with the aggregate attributes of the solid itself. Debris such as metals, glasses, and ceramics are accepted as 'hard solids' because the actinic bonds that authority them calm (e.g., covalent, ionic, or metallic) are actual strong. Thus, it takes a ample ascribe of activity to breach these debris so they are termed “high energy.” Most atomic liquids accomplish complete wetting with high-energy surfaces.
The added blazon of debris is anemic atomic crystals (e.g., fluorocarbons, hydrocarbons, etc.) area the molecules are captivated calm about by concrete armament (e.g., van der Waals and hydrogen bonds). Since these debris are captivated calm by anemic armament it would yield a actual low ascribe of activity to breach them, and thus, they are termed “low energy.” Depending on the blazon of aqueous chosen, low-energy surfaces can admittance either complete or fractional wetting.34
edit Wetting of low-energy surfaces
Low-energy surfaces primarily collaborate with liquids through burning (van der Waals) forces. William Zisman had several key allegation in the plan that he did:5
Zisman empiric that cos θ increases linearly as the apparent astriction (γLV) of the aqueous decreased. Thus, he was able to authorize a boxlike affiliation amid cos θ and the apparent astriction (γLV) for assorted amoebic liquids.
A apparent is added wettable if γLV is low and if θ is low. He termed the ambush of these curve if the cos θ = 1, as the analytical apparent astriction (γc) of that surface. This analytical apparent astriction is an important constant because it is a appropriate of alone the solid.
Knowing the analytical apparent astriction of a solid, it is accessible to adumbrate the wettability of the surface.1
The wettability of a apparent is bent by the exoteric actinic groups of the solid.
Differences in wettability amid surfaces that are agnate in anatomy are due to differences in packing of the atoms. For instance, if a apparent has angled chains, it will accept poorer packing than a apparent with beeline chains.
The added blazon of debris is anemic atomic crystals (e.g., fluorocarbons, hydrocarbons, etc.) area the molecules are captivated calm about by concrete armament (e.g., van der Waals and hydrogen bonds). Since these debris are captivated calm by anemic armament it would yield a actual low ascribe of activity to breach them, and thus, they are termed “low energy.” Depending on the blazon of aqueous chosen, low-energy surfaces can admittance either complete or fractional wetting.34
edit Wetting of low-energy surfaces
Low-energy surfaces primarily collaborate with liquids through burning (van der Waals) forces. William Zisman had several key allegation in the plan that he did:5
Zisman empiric that cos θ increases linearly as the apparent astriction (γLV) of the aqueous decreased. Thus, he was able to authorize a boxlike affiliation amid cos θ and the apparent astriction (γLV) for assorted amoebic liquids.
A apparent is added wettable if γLV is low and if θ is low. He termed the ambush of these curve if the cos θ = 1, as the analytical apparent astriction (γc) of that surface. This analytical apparent astriction is an important constant because it is a appropriate of alone the solid.
Knowing the analytical apparent astriction of a solid, it is accessible to adumbrate the wettability of the surface.1
The wettability of a apparent is bent by the exoteric actinic groups of the solid.
Differences in wettability amid surfaces that are agnate in anatomy are due to differences in packing of the atoms. For instance, if a apparent has angled chains, it will accept poorer packing than a apparent with beeline chains.
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