surface properties exam 1 Flashcards
what are surface properties equally important as
bulk properties - can be very different due to unbalanced interactions
where do most biological responses occur
on the interface between biomaterials and biological systems at molecular (nano) and cellular (micro) levels
what does attenuation (reduction) of bonding lead to
unfulfilled strong and weak interactions
why do molecules/atoms on the surface have excess free energy
because of unbalanced interfacial/surface forces
what has a high surface energy
corners and tips because there are random shapes and higher area
how is critical surface tension (CST) determined
by dropping a series of liquids of known surface tension on the unknown biomaterial surface for extrapolation
what does the Zisman theory define
the surface tension of a solid material as being = to the surface tension of the highest (or lowest) surface tension liquid that wets the solid material surface completely
what does a goniometer do
camera takes picture of image and software takes measurements over time to determine contact angle
what is cst
critical surface tension - highest surface tension with a 0 degree angle where liquid wets solid material completely
what is the sliding angle
tells how sticky a surface is; low sliding area = easier to move slides
what does contact angle show
how strong water repellent properties are - better CA = better performance
what are mechanical surface properties
interfacial/surface tension, modulus, wear resistance
what are chemical surface properties
hydrophobicity/hydrophilicity, composition, interfacial/surface energy, reactivity, corrosion resistance
what are topographical properties
roughness, morphology/shape, curvature
what are electrical properties
charge density, electron density
