Due to the trend of multi-function, integration, and miniaturization of electronics, traditional dielectric materials are difficult to satisfy new requirements, such as balanced dielectric properties and good designability. Therefore, high dielectric polymer composites have attracted wide attention due to their outstanding processibility, good designability, and dielectric properties. A number of polymer composites are employed in capacitors and sensors. All these applications are directly affected by the composite’s dielectric properties, which are highly depended on the compositions and internal structure design, including the polymer matrix, fillers, structural design, etc. In this review, the influences of matrix, fillers, and filler arrangement on dielectric properties are systematically and comprehensively summarized and the regulation strategies of dielectric loss are introduced as well. Finally, the challenges and prospects of high dielectric polymer composites are proposed.

The advent of high frequency communication era presents new challenges for further development of dielectric polymer materials. In the field of communication, efficient signal transmission is critical. The lower the dielectric constant of the dielectric material used, the lower the signal delay and the higher the signal fidelity. The preparation of polymer materials with low dielectric constant or reduce the dielectric constant of polymer materials becomes a key research topic. Summarizing past progress and providing perspective, this paper primarily discusses the intrinsic low dielectric polymers, fluorine doped low dielectric polymers, and microporous low dielectric polymers, while predicting the research trend of low dielectric materials.