Contact Angle

Contact Angle Goniometry

Technique:
The angle at which a liquid interface meets a solid surface is called the contact angle. When a liquid has a low contact angle, the liquid is attracted to and will spread out onto the solid surface. Consequently, when a liquid has a high contact angle, the liquid is repelled from and will create a bead of liquid on the surface. Contact angle goniometry is used to measure this angle.

Instrument:
Ramé-Hart Contact Angle Goniometer with an optical system and micro-syringe attachment

Measurement Capabilities:

  • Static and dynamic drops
  • Advancing and receding contact angles
  • Surface tension
  • Surface free energies
  • Optical system to capture the profile of the liquid on the solid surface

Selected Applications in Industry:

  • Can give important information about the surface of a solid.
  • Can give physical properties of interaction between the solid and liquid like wettability, affinity, adhesiveness and repellency.
  • Advancing and receding contact angles can characterize heterogeneity, roughness and mobility.
  • Can be used to evaluate the cleanliness of a solid surface.