Preparation, Surface Characteristics, and Electrical Conductivity of Flexible CA/TiO ₂ Nanocomposite Films for Dielectric Applications

In this work, the composites CA/TiO 2 , composed of cellulose acetate (CA) with different concentrations of titanium dioxide (TiO 2 ) nanoparticles were successfully fabricated. The structural and morphological characteristics of the prepared CA/TiO 2 nanocomposites were investigated using SEM, TEM, and EDX techniques. The EDX and mapping analyses confirmed the successful incorporation and homogeneous distribution of TiO 2 within the CA matrix. Morphological observations from SEM and TEM revealed well dispersion of TiO 2 with CA. The electrical conductivity increased from 8.27 × 10 −13 S.cm −1 for CA to 18.9×10 −13 S·cm −1 for the CA/TiO 2 nanocomposite at frequency of 100 Hz. The conductivity value representing a modest enhancement attributed to improved charge carrier mobility and interfacial interactions introduced by the TiO 2 nanoparticles. Surface free energy was further evaluated through contact angle measurements using water and diiodomethane liquids. The contact angle reduced from 65.3° for CA to 52.4° for CA/TiO 2 with water and from 58.4° to 45.3° for diiodomethane. These changes are attributed to the formation of new surface functional groups and alterations in surface morphology induced by the nanoparticle incorporation. The obtained results demonstrate the CA/TiO 2 nanocomposite exhibit improved electrical and surface characteristics, suggesting applying these materials for dielectric applications.