Atmospheric Plasma Treatment of Polyethylene Substrates for Improved Mechanical Performance of Adhesion Joints

Abstract

Most industrial polymers and composites have low surface free energy and lack polar functional groups on their surface, resulting in a class of materials with poor adhesion properties. Currently, used chemical or physical processes have a number of drawbacks as they use products that harm the environment. An alternative to these processes is the treatments using plasma technologies. The equipment plasma was situated in a stand, making it possible to modify the distance between the sample and the nozzle. In addition is possible to vary the feed speed of the sample with an adjustable speed drive. Therefore are analyzed the chemical and physical processes that occur on the surface of polyethylene increase its adhesive properties changing the feed speed and distance between the sample and nozzle. The adhesive properties were evaluated by peeling tests. The results show that at low speeds and distances, the polar molecules are grafted in the surface of polyethylene giving a higher superficial modification.