Pinhole Effect and Formation of Microplastics on PVC, PP and PET Surfaces Initiated by Plasma

The aim of the study is to test the ability of PVC, PP, and PET polymer films to withstand the conditions present on a planar ceramic dielectric. The planar ceramic dielectric generates DCSBD plasma, which is also known as cold plasma. During its generation/excitation, the ceramic dielectric is fully covered by pulsating electrical microdischarges. At the same time, an increased temperature is observed on the ceramic dielectric, which can potentially cause shape deformation (typically undesired) in thermoplastics. It is ideal for thin polymer films of thermoplastics, after modification by DCSBD plasma, not to be affected in such a way and not to exhibit small holes on their surfaces. The formation of these holes is referred to as the pinhole effect or pinholing effect. These holes are very small, but under certain process conditions, they can enlarge until they merge into a single large hole. It has been observed that in the vicinity of these holes and even in remote areas of the surfaces of these thermoplastics, the formation of particles can occur, which can be simplified classified as microplastics upon initial examination. Therefore, the study also provides quantification of these particles in the context of observing their size, the recorded pinhole effect, pulsating electrical microdischarges, in both filamentary and diffuse regions of DCSBD plasma.