Increasing the surface quality of recycled components by means of plasma coating
In a joint research project, the SKZ Kunststoff-Zentrum and Fraunhofer IFAM are investigating the possibilities for improving the surface properties of recycled plastics with regard to adhesive applications. Activation and coating processes with atmospheric pressure plasma are the means of choice for this.
Plastic components made from recycled material or with a defined recycled content often exhibit considerable fluctuations in their material composition due to the material and the process, which leads to inhomogeneous and fluctuating surface properties. Reasons for this are a varying molecular weight distribution of the recycled plastic, the loss of stabilizers and other functional additives, and possible contamination with foreign material. As a result, downstream process steps - such as bonding, painting, printing and coating - are prevented or made more difficult because they are based on defined and consistently adhesion-friendly surface qualities.
The aim of the joint project of the SKZ Plastics Center and Fraunhofer IFAM is to promote the use of recycled materials for surface-specific manufacturing processes by adapting the surface properties. This is to be achieved by atmospheric pressure plasma pretreatment processes and deposition of an adhesion-promoting layer by means of plasma polymerization (PECVD - Plasma Enhanced Chemical Vapor Deposition). In this process, the surface variance of the recycled surfaces is leveled out so that an adhesion increase for subsequent bonding is achieved. In addition, a migration barrier for additives from the recyclates is possible. Interested companies are welcome to contact the SKZ with specific questions and suggestions. Project 22619 N of the FSKZ e.V. research association is funded by the German Federal Ministry of Economics and Climate Protection (BMWK) via the German Federation of Industrial Research Associations (AiF) as part of the program for the promotion of joint industrial research (IGF) on the basis of a resolution of the German Bundestag.