Toward high dielectric constant and low dielectric loss nanocomposite via kinetical migration

作者：Zhang, Huanhuan; Jiang, Haowei; Huang, Zhao-Xia^*; Qu, Jin-Ping^*

来源：Composites Science and Technology, 2022, 221: 109310.

DOI：10.1016/j.compscitech.2022.109310

• Nanocomposites
• Dielectric properties
• Microstructure
• Kinetical migration

Controlling the selective localization of nanoparticles in an immiscible polymer blend is a promising concept for developing high-performance polymeric dielectrics. However, the mechanism of the dielectric regulation has not been lucidly studied. In this work, PLA/PVDF/CNTs nanocomposites with tunable dielectric properties were fabricated via tailoring the localizations of CNTs based on kinetic-based approach. The dielectric evolutions were attributed to the synergistic effects of the "sea-island" structure, and the number and average capacitance of the microcapacitors in PLA/PVDF/CNTs nanocomposites. Ultimately, we obtained the PLA/PVDF/CNTs nano composites with a high dielectric constant of 956.6@1 kHz, which was more than 100 times higher of the virgin PVDF, at a very-low dielectric loss of 0.17@1 kHz. Since the interface interaction was enhanced by locating CNTs at interface, the highest tensile strength of nanocomposites fabricated by two-step method reached 59.1 MPa at a mixing time of 12 min. This work not only reports a high-performance polymeric dielectric with a high dielectric constant and a low dielectric loss, but also intends to propose a general insight in the effect of kinetically regulated migration of conductive fillers on the as-prepared nanocomposites.