Flexible chitin/CCTO composite films for dielectric capacitor: The influence of filler morphological structure

With the continuous development and progress of science and technology, the widespread use of petroleum-based plastics has highlighted serious environmental issues. Scientists are committed to replacing some of the applications of petroleum-based plastics with sustainable natural polymer materials. Chitin, cellulose, and other natural polymers rich in polar groups are suitable for designing and preparing sustainable and low-polluting dielectric energy storage materials. In this study, we selected calcium copper titanate (CCTO) with ultra-high dielectric constant as a dielectric enhancement filler and explored the effects of different morphological structure fillers on the dielectric energy storage properties of composite films. CCTO nanoparticles and CCTO nanofibers were mixed with chitin solution and cast into chitin/CCTO composite films. The one-dimensional CCTO nanofibers showed a more significant improvement in the comprehensive performance of the composite films. When the addition amount was 3 wt%, the breakdown field strength of the composite film was 410 MV m −1 , the charge-discharge efficiency was 78.2 %, and the energy storage density reached 6.14 J cm −3 , showing an obvious improvement compared with the pure chitin film and chitin/CCTO nanoparticles composite films. It is possible that the high aspect ratio structure fillers can enhance the inhibition of electric branches and provide better compatibility with the matrix.