Photo: Barzandr, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons
Plasma technology - Modifying the surface properties of materials
The technological progression in the world is moving fast, imposing ever more demanding requirements on the materials that will furnish the future. A tool for meeting these demands is the ability to modify the surface properties of a material. As the surface of a material often is the first point of interaction, modification of surface properties is a key aspect of improving material performance overall. In the case of polymeric materials used in sealing solutions, techniques using plasma technology appear particularly promising.
Plasmas can be generated with a wide range of gases, combining this with a vast variety of process conditions, the possibilities for surface modification are numerous. At Seal Engineering, our main concern is providing our customers with sealing solutions with the best performance available. In order to reach this goal, we have now entered the world of plasma surface modification.
Plasma technology unlocks the ability to modify surfaces in various ways. The main techniques can be summarized as:
- Cleaning
- Activation
- Etching
- Coating deposition
Plasma cleaning provides a high degree of organic contaminant removal, and may be used for sterilization of medical equipment. Careful selection of process gases can even enable the cleaning of more resilient contaminants like silicone, which as a contaminant can be detrimental to paint and varnish application. Plasma activation introduces functional chemistry to a surface. The functionalization leads to improved adhesion between bonded parts, or between a part and an applied coating. In the fabrication of integrated circuits, plasma etching is already widely used. Functional coatings can be deposited using plasma to supply the energy needed to obtain the desired surface reactions for film growth. The coatings introduce new functionality to the surface, such as:
- Improved frictional performance
- Reduced wear
- Modified wettability (i.e. hydrophobic coatings)
- Gas transmission barriers
- Enhanced corrosion resistance
These processes can be attained with various types of plasma equipment. Central examples include flexible systems operating in atmospheric pressure, as well as low-pressure systems in which a secluded vacuum chamber offers a high degree of control over process parameters. The parts to be treated can be of virtually any material. In fact, gentle processing conditions in a low-pressure plasma system permit treatment of materials that traditionally are too delicate for harsher thermal treatment techniques.
