Flexible Low Dielectric Polyimide/Fluorinated Ethylene Propylene Composite Films for Flexible Integrated Circuits

Comparative Study of Anti-Sticking Properties of Coatings for Tire Molds

“…As the surface of PTFE resin is inert, the contaminants do not easily deposit on its surface, but the fibrous structure of PTFE increases the penetration of hot rubber material, causing large demolding force. PFA and FEP have lower crystallinity than PTFE, and their melt viscosities at 380 °C are 10 7 -10 8 Pa•s and 10 3 -10 5 Pa•s, respectively, which are much lower than that of PTFE, around 10 10 Pa•s [24][25][26]. Thus, the surfaces of the PFA and FEP coatings are smoother than that of the PTFE coating, resulting in lower demolding force (as shown in Figure 6).…”

“…FEP is a copolymer of TFE and hexafluoropropylene (HFP). It is essentially PTFE with an occasionally trifluoromethyl (-CF 3 ) side group attached [25,26]. It can be seen that the carbon chains of the three fluororesins are surrounded by fluorine atoms, which is the most electro-negative and least-polarizable element known.…”

Carbon nitride/polyimide porous film via an NIPS method with advanced dielectric and hydrophobicity properties

“…13 Based on previous research, there are three efficient ways to achieve PI lms with a low dielectric constant or dielectric loss: design of the chemical structure by adding groups with large free volume or strongly polar uorine elements; 14 the introduction of an air-porous structure into the polymer matrix since air is the substance with the lowest dielectric constant of 1.0; 8,15 blending with uorine-containing llers, such as uorographene [16][17][18][19] or uorinated ethylene propylene (FEP) nanoparticles. 20,21 The design of the chemical structure is usually very costly and causes a decrease in the glass transition temperature (T g ) of PI. The latter two ways are currently identied as being more practical approaches to obtain PI substrates with a low dielectric constant.…”