Mechanically Robust Fluorinated Graphene/Poly(p-Phenylene Benzobisoxazole) Nanofiber Films with Low Dielectric Constant and Enhanced Thermal Conductivity: Implications for Thermal Management Applications

Abstract

Low-dielectric materials have found broad applications in microelectronics but are limited by poor mechanical properties and thermal conductivity. In this study, a class of nanocomposite films based on fluorinated graphene (FG) was developed by replacing the traditional polymer matrix with a 3D interconnected poly(p-phenylene benzobisoxazole) (PBO) nanofiber network. The FG nanosheets are uniformly distributed in the porous network of PBO nanofibers (PBONF) and stacked orderly to form a nacre-like layered structure while paving effective thermal conduction paths. Ultimately, the strong interfacial bonding and efficient synergy between FG and PBONF endow the composite films with unparalleled tensile properties (strength and modulus up to 295.4 MPa and 7.79 GPa, respectively) and folding endurance (no drop in tensile properties after 1000 folds), ultralow dielectric constant (as low as 1.71), and excellent thermal conductivity (12.13 W m–1 K–1). In addition, these FG/PBONF composite films also exhibit an ultrahigh thermal stability (5% weight loss temperature higher than 540 °C), which makes them promising for the heat dissipation of high-power electronic devices in extreme environments.

Bottom-Up Strategy toward Heterocyclic Aramid Nanofibers and Their Application in Strengthening Poly(p-phenylene benzodioxazole) Paper via Constructing a Bilayer Asymmetric Structure

“…With the rapid development of microelectronic devices in the direction of light weight, miniaturization, and high performance, it is urgent to reduce the dielectric constant of the dielectrics to alleviate problems such as electronic crosstalk and capacitive signal delay. , PBO paper has attracted a lot of attention in civil and military industries such as printed circuit boards and electric power because of its excellent insulation. , The dielectric constant and electrical breakdown strength of the composite paper were tested to analyze the effect of HANFs on the insulation of PBO paper. As shown in Figure a, the porous PBO paper has an extremely low dielectric constant of 1.33 at 1 MHz due to the large amount of air it contains.…”

“…32,33 PBO paper has attracted a lot of attention in civil and military industries such as printed circuit boards and electric power because of its excellent insulation. 34,35 The dielectric constant and electrical breakdown strength of the composite paper were tested to analyze the effect of HANFs on the insulation of PBO paper. As shown in Figure 10a, the porous PBO paper has an extremely low dielectric constant of 1.33 at 1 MHz due to the large amount of air it contains.…”