Synthesis and Properties of Novel Polyarylates Containing Furan Pendent Groups and Reversibly Crosslinked structure

Abstract

Low dielectric polymers are urgently needed in wireless communication. Compared with porous structure, the introduction of free volume can reduce the dielectric constant without damage the mechanical properties. Therefore, a new kind of low dielectric constant polyarylates with furan as the reactive pendent groups (PAFRs) were innovatively designed and synthesized based on furfural. The introduction of pendent furan groups was found to increase the free volume and molecular chain space that further affect the dielectric properties. The dielectric constant and dielectric loss of PAFRs decreased down to 2.57 - 2.92 and 0.005 - 0.0091 at 1 MHz, respectively, with excellent thermal (T_g > 209 ^oC) and mechanical properties (Tensile strength > 73 MPa). Furthermore, reversible crosslinked low dielectric constant polyarylates (C-PAFR) were designed and prepared by dynamic covalent based on pendent furan groups. The crosslinked structure further reduced the dielectric constant as the dielectric constant of crosslinked PAFR films (C-PAFR23) could even decrease down to 2.17. In addition, the dynamic crosslinked structure endowed C-PAFRs with excellent solvent resistance and good re-processability with the on/off Diels-Alder reaction. We believe such recyclable dynamic crosslinked low dielectric materials are interesting and would be applicable in the field of wireless communication.