top of page
  • Writer's pictureDavide

Plasma Surface Activation: Learn About What It Is and How It Works

Vacuum plasma surface activation is a cutting-edge technique that significantly improves the adhesion properties of various materials, paving the way for enhanced bonding, gluing, coating, and painting applications. This innovative process involves replacing surface polymer functional groups with different atoms, thereby increasing the surface energy through the utilization of vacuum plasma technology.

Plasma surface activation effects can last anywhere from a few minutes to several months, depending on the material and intended usage. Widely employed in industrial processes for surface functionalization, plasma activation offers a cost-effective, safe, and environmentally friendly alternative to conventional methods.

In this article, we will go through the ins and outs of vacuum plasma surface activation, exploring the process, its workings, and the different types of plasma. With this knowledge in hand, you can make an informed decision on whether this advanced technique is the right fit for your specific needs.

What is Plasma Activation?

Adhesive bonding with low-surface energy materials, such as polymers, can pose challenges in achieving high-strength bonds. Vacuum plasma surface treatment offers an effective solution by preparing the material's surface before adhesive bonding. This process not only removes organic contaminants but also enhances the bondability of the surface.

Vacuum plasma surface activation chemically prepares the topmost surface layer of the material by increasing its surface energy which will allow the adhesive to bond effectively even at the smallest scale. This technique stands out for its ability to achieve all necessary activation objectives in a single step, without the use of toxic chemicals.

It offers a simple, versatile, and environmentally friendly surface preparation method that consistently delivers reliable bonding results.

How Does Plasma Activation Work?

When a material surface is exposed to plasma, the plasma ions and radicals can react with the surface atoms of the materials. Chemical reactions are induced in the material surface, which modify the hydrophily of the surface functional groups and create free radicals.

The plasma also generates UV radiation, which further produces free radicals on the surface. These free radicals rapidly react with the material, forming stable covalent bonds with the material to be bonded.

Plasma surface activation works best for materials like plastics and rubber that are used in many different industries, including medical devices, consumer electronics and transistors, car parts, and even airplanes.

3 Types of Plasmas Used in Surface Activation

There are 3 basic types of plasma activation technologies. These differ by how the plasma is generated.

1. Piezoelectric direct discharge (PDD)

Piezoelectric direct discharge (PDD) plasma is a type of non-thermal plasma generated using piezoelectric materials and a gas at atmospheric pressure. Piezoelectric materials possess unique properties that allow them to generate an electric charge in response to mechanical stress or strain. PDD plasma is created by applying high-frequency electrical signals to piezoelectric materials, which in turn generate a high electric field that ionizes the surrounding gas and produces plasma.

The generation of PDD plasma does not require additional external electrodes, as the piezoelectric material itself acts as the electrode. This makes the PDD plasma generation process relatively simple and compact compared to other plasma generation methods.

2. Dielectric barrier discharge (DBD)

Dielectric Barrier Discharge (DBD) is a type of non-thermal plasma discharge that occurs between two electrodes, at least one of which is covered by a dielectric material, in a process gas at atmospheric pressure. The dielectric material acts as a barrier, preventing the formation of a continuous current arc between the electrodes, which in turn results in a series of micro-discharges or filaments.

DBD is generated by applying a high voltage across the electrodes, creating an electric field that ionizes the gas between them. The dielectric barrier helps to limit the current flow and maintain the non-thermal or cold plasma state. In this state, the gas temperature remains relatively low, while the electrons are highly energized.

3. Vacuum plasma activation

Vacuum plasma activation is a surface modification process that uses plasma in a vacuum environment to alter the surface properties of a material. The primary goal of this technique is to enhance the adhesion properties of materials, making them more receptive to bonding, coating, or printing processes.

The vacuum plasma activation process involves placing the material to be treated inside a vacuum chamber and evacuating the air. A suitable process gas is then introduced into the chamber, and an electrical discharge is used to generate plasma. The plasma consists of highly reactive ions, electrons, and radicals, which interact with the surface of the material, altering its chemical composition and creating a higher surface energy.

As a result, the treated surface becomes more adhesive and suitable for various applications, such as bonding, gluing, coating, and painting.

Is Plasma Surface Activation Right For Your Needs?

Because there are so many different types and variables associated with Plasma Surface Activation, it is best to speak directly with a team of experts. Whether one is interested in plasma surface treatment, plasma bonding, plasma cleaning, or other techniques, SCI Plasma has the professional knowledge to deliver the best advice. SCI Plasma has expertly written guides in addition to its plasma bonding equipment. With decades of combined experience, SCI Plasma is a global leader in this competitive field. They also offer the finest customer service for any needs within this scope.

Plasma surface activation is environmentally friendly and cost-effective. It is best used on plastics and rubber materials used in many industries, such as medical devices, consumer electronics, car parts, and airplanes. It is best to consult with a team of experts like SCI Plasma for advice on plasma surface treatment, bonding, and cleaning techniques.

bottom of page