Highly thermostable high molecular-weight low k PIM polymers based on 5,5′,6,6′-tetrahydroxy-3,3,3′,3′-Tetramethylspirobisindane, decafluorobiphenyl, and bisphenols

[摘要] High-molecular-weight (number average molecular weight M-n = 11-81 kDa) polymers with intrinsic microporosity (PIM) were prepared by the solution polycondensation of 5,5,6,0-tetrahydroxy-3,3,3',3'-tetramethyl-1,1'-spirobisindane, decafluorobiphenyl, and bisphenols in an aprotic polar solvent at an initial monomer concentration of 0.1 mol/L at 100 degrees C-140 degrees C for 10-144 h. Transparent (minimum cutoff wavelength of 310 nm), highly thermostable (glass transition temperature of 161 degrees C-376 degrees C by dynamic mechanical analysis, and 5% weight loss temperature in N-2 of 410 degrees C-514 degrees C) polymer films were fabricated using a solvent-cast method. The copolymer films showed good mechanical properties (tensile strengths of 45-67 MPa, breaking elongation of 2.2%-23.1%, and tensile elastic moduli of 1.5-3.3 GPa) and insulating properties (relative permittivity of 2.27-2.59, and dissipation factor of 0.00191-0.00466 at 20 GHz frequency). The prepared new PIM copolymers are candidates for next-generation low k dielectric materials.

[发布日期] 2021-09-16

[关键词] Polymer of intrinsic microporosity;Decafluorobiphenyl;Low dielectric constant material