A Geometry-Driven Modeling Framework for Matrix-Filler Interactions Governing Dielectric Response and Electrical Conductivity in Composite Materials

The interaction between filler and matrix materials in a composite structure significantly influences the effective performance of electronic devices employed in capacitive and resistive applications. In this study, a theoretical model is proposed to describe filler-matrix interactions as a function of geometric factors, considering filler alignment along both electrode and non-electrode directions. The effective capacitance and resistance of the composite are examined with respect to filler shape, and orientation. Geometric parameters, including filler length and cross-sectional area, are shown to strongly affect the overall dielectric response and conductive properties of the composite. Inclusions aligned along the electrode direction enhance capacitance while reducing resistance, with spherical fillers exhibiting a greater effect than cubic fillers due to their geometry. The proposed model is benchmarked against classical effective medium theories, demonstrating that filler orientation can be used to tune dielectric and conductivity response. Electrical parameters can be tailored by varying filler geometry and alignment within the matrix. This new model provides a foundation for designing advanced composite materials, where filler orientation can be precisely controlled using modern fabrication approaches such as 3D printing, enabling improved performance in electrical and electronic device applications.