Plasma polymerisation is a coating process used to deposit thin polymer films or a plasma polymer composite onto substrates. Plasma polymer composites refer to films which are formed by incorporating particles, fibres, or other materials into the polymer matrix during the process of plasma polymerisation, which results in a composite material with enhanced functionalities.
The plasma polymerisation process begins with introducing a precursor gas into a vacuum chamber containing the substrate which is to be coated. The precursor gas is a monomer or mixture of monomers, which are typically organic compounds that can undergo polymerisation reactions. Some common precursor gases used in plasma polymerisation include hydrocarbons, fluorocarbons and silanes.
With the precursor gas in the vacuum chamber, a plasma is generated by applying an electric field to the gas. The plasma dissociates the precursor gas molecules and produces a reactive species such as electrons, ions and free radicals. These species react with the substrate surface, forming a polymer film. The deposition of polymer films in plasma polymerisation is a self-limiting process because the growth rate of the film decreases as the film thickness increases. This article describes the process in greater detail:.
Advantages of plasma polymerisation
One advantage of plasma polymerisation is its ability to deposit polymer films with controlled properties. The properties of the polymer films, such as their chemical composition and thickness can be modified by adjusting process parameters, such as the composition of the precursor gas, plasma power, pressure, and deposition time. This makes plasma polymerisation a versatile technique that is used to tailor the properties of polymer films for many applications, including coatings, barrier layers, adhesion promotion and biomedical coatings. You can find out more information about plasma polymer composites and their uses here: https://www.poeton.co.uk/advanced-treatments/apticote-810-plasma-polymer-composite/.
To summarise, plasma polymerisation is a surface modification technique that uses plasma-generated species to deposit thin films of polymers onto substrates. It is used to produce surfaces that are non-stick, low-friction, resistant to wear, corrosion and temperature. It is used in many different industries thanks to its versatility and ability to tailor the properties of the polymer films for specific requirements.