An organic dielectric filler polyethylene glycol-polyaniline block copolymer with low-density used in PVDF-based composites

In order to meet the ever-increasing demand for lightweight and flexibility with the development of aeronautics, astronautics and wearable technology, dielectric ceramics are inappropriate for the polymer-based dielectric materials due to their high density. An organic semiconductor material polyethylene glycol-polyaniline multi-alternating block (more than triblock) copolymer (with a low density ∼ 0.9 g/cm3) was designed. This polymer had a good solubility in polar solvents (e.g. DMF and DMSO) which could provide it with a good processing performance and a good dispersion in PVDF matrix. Its alternating block structure had a special role in the charge transport of PANI segments, providing composites with high dielectric constant and overcoming the poor breakdown strength problem of conductive filler-based dielectric composites, even better than BaTiO3. The breakdown strength of PEG-PANI/PVDF composite was 10.74 kV/mm and the dielectric constant was 86.64 (100 Hz) at 20 vol%, better than BaTiO3/PVDF (9.89 kV/mm and 45.23).