Development of Multilayer Flexible Polyethylene–Graphite Film for Electromagnetic Interference Shielding

ABSTRACT

This paper presents the development of lightweight multilayer polyethylene (PE)–graphite (Gr) films with enhanced electromagnetic interference (EMI) shielding properties using an adhesive‐free calendaring approach, and a transmission‐line‐based mathematical model is proposed, accounting for graphite surface resistance as a function of total layer numbers. Film morphology was characterized through scanning electron microscopy, confirming robust interlayer adhesion even in five‐layer configurations, while through thermogravimetric analysis graphite content was quantified below 5 wt%; substantially lower than conventional EMI shielding composites. Electromagnetic properties, including shielding effectiveness, reflectance, absorbance, and transmittance, were evaluated using a vector network analyzer. The model accurately predicts observed electromagnetic behavior. Compared to neat PE, EMI shielding performance improved significantly: a single Gr‐PE layer approached theoretical absorption maxima, and five‐layer films achieved approximately 20 dB shielding with minimal graphite loading, fulfilling industrial standards.