Preparation of Barium Titanate/Polyimide Composite Film and its Dielectric Properties

Polyimide (PI) was chosen as the matrix of the composites, barium titanate/polyimide (BT/PI) nanocomposite films were prepared with in-situ polymerization. The morphology of the samples was obtained by SEM. The factors affecting the dielectric properties are discussed. When the mass fraction of BT is 70%, the dielectric constant will be 19.32, and loss 0.00254 (at 10 3 Hz). The optimal solvent content and ultrasonic time were 9.2 ml and 30 min respectively. TG analysis shows that the film is stable below 500°C. The AC breakdown strength were 42 MV·m -1 and 64 MV·m -1 for 70% BT/PI and 60% BT/PI respectively, and corresponding energy storage density were 0.17 J·cm -3 and 0.30 J·cm -3 respectively.