Tailored polyphenylene sulfite composite with desirable mechanical performance and low dielectric constant by constructing a controllable aramid fiber network

With an increasingly complex working environment and the growing demand in the electrical equipment market, the performance of high-frequency printed circuit boards (PCBs) is generally inadequate, and this problem is due to the failure of either its material or internal architecture. Thus, state-of-the-art PCBs with robust mechanical performance and a low dielectric constant need to be developed. This study proposes a facile technique to fabricate PCBs by assembling aramid fiber (AF) and polyphenylene sulfide (PPS) by combining papermaking and thermocompression lamination. A PPS nonwoven fabric and AFs were first introduced into deionized water and then subjected to intense shearing to form hybrid paper. AF/PPS composite laminates were then fabricated by thermocompression. The as-prepared AF/PPS-30 wt% sample exhibited a flexural strength of 181.4 MPa and a flexural modulus of 13.1 GPa. The sample also achieved a dielectric constant of 3.3 at 15 kHz to 2 MHz, suggesting that the sample exhibited superior dielectric performance and frequency independency as a high-frequency function attributable to the controllable aramid network structure. The dielectric constants of one-dimensional materials reinforced polymer composites were also studied theoretically, and the results presented using the Bruggeman model were consistent with the experimental values. This study provides a feasible strategy for the fabrication of extraordinary PCBs to achieve both desirable mechanical performance and low dielectric constant.