General about non-stick coatings
The low adhesion tendency, or rather the non-stick effect of fluoropolymers such as PTFE, PFA or FEP, depends on their extremely low surface energies. PFA and FEP are copolymers of PTFE. By the theoretical view of the Water contact angle and the resulting balance of forces of adhesion and cohesion for the fully fluorinated plastics, such as PTFE, PFA, and FEP, give values for the same excellent non-stick properties. In the rarest cases, pure PTFE, PFA or FEP are rarely used for coating. Usually, coatings are characterized in that for adhesion improvement, a so-called primer layer, or even a primer system, which may consist of several layers, applies. In the overall coating systems, adhesion promoter additives, pigments, heat stabilizers and a wide variety of binder resins are combined. Selection and mixing ratio of the components as well as their layer structure determine then the function and the efficiency of a system. This structure applies to both PTFE-, PFA-, as well as for FEP systems.