Fabrication of low dielectric constant fluorinated poly(arylene ether nitrile) composites by cross-linking with metal-organic frameworks

The communication industry has been developing rapidly, but there is still a huge challenge in low dielectric materials. Porous polymer materials have been extensively studied as low dielectric materials. However, their application is limited by poor mechanical properties, high water absorption, etc. In this work, fluorinated poly(arylene ether nitrile) containing carboxyl groups (PEN) are designed and synthesized and then MOF-3 is used as a nanoporous filler and crosslinker. Through simple heat treatment, cross-linked networks are constructed and the overall performance of the composite films has been significantly improved. Benefiting from the introduction of cross-linked networks and the porous structure of MOF-3, the dielectric constant of PEN-M-3 composite films is as low as 2.33 at 1 MHz, and the water uptake is as low as 0.126%. In addition, all the composite films have excellent thermal stability (T5% > 490 °C) and outstanding mechanical properties (tensile strength > 82 MPa). Such excellent performance will have the potential to be applied to low dielectric materials, and this strategy will also provide a new approach for the design and preparation of low dielectric materials.