Every wonder how to measure plastic materials to determine surface energy and tension properties? The process is easier than you might imagine, and can lead to better manufacturing outcomes through plasma surface treatment.
As a quick review, surface energy is the sum of all the molecular forces on the surface of a plastic material. It also covers the amount of repulsion or attraction of one material as exerted by another. A goniometer is used to measure surface energy and tension angles. It’s critical that the surface energy and the surface tension are aligned before moving to plasma treatment. If the surface energy of a material is too low, then coatings will not flow and may form defects such as pinholes or fisheyes. If the surface energy it too high, the added liquids (inks and paints) may bleed.
Why is material surface energy important to know in manufacturing?
Understanding surface energy and tension properties are the precursors to a plasma surface treatment. With plasma, you can extend the performance of secondary manufacturing processes such as ink stamping or bonding. Plasma can help many industries overcome common manufacturing challenges. In medical manufacturing, for instance, plasma treatment of syringes allows us to add calibration marks for more-accurate dispensing of medicines. In aerospace, plasma treatment gives wing edges strong adherence for better wind resistance.
Here’s a simple formula for liquid testing of surface properties:
Spreading = A - ( B+ C )
A = surface energy of solid (given below)
B = surface tension of liquid
C = surface energy of solid-liquid interface
If spreading is:
Negative - liquid will bead up
Zero - liquid will spread
Positive - liquid will spread
Want to explore more about the surface energy and surface tension of plastics? Ask the Experts for a recommendation, or check out our brief video below for a demo!