Vapor Phase Infiltration Modulating Microwave Absorption of Conductive Polymers: Frequency Tunability and Polarization Enhancement

as the precursor, PEDOT:PSS-coated polypropylene foams are infiltrated under systematically varied VPI cycles and exposure durations. Adjusting the infiltration parameters allows the permittivity to be finely tuned, resulting in a distinct low-frequency shift of the absorption peak. The results show that prolonged exposure time promotes deeper infiltration of the precursor and the formation of nano-scale Ti-containing hybrid domains in the matrix, which strengthens the coupling of organic-inorganic interfaces, thereby promoting dipole polarization and interface polarization. This study combines theoretical calculations with experiments to elucidate the intrinsic mechanism of enhanced electromagnetic wave attenuation through VPI, offering new insights for regulating the dielectric behavior of conductive polymers.