Synthesis and evaluation of phosphonated poly(4-phenoxybenzoyl-1,4-phenylene)

Poly(4-phenoxybenzoyl-1,4-phenylene) (PPBP), which has high thermal stability and mechanical properties, was phosphonated by the three-step reaction. The phosphonated PPBP (P-PPBP) was characterized by FT-IR, 1 H-NMR, elemental analysis, and ICP emission spectroscopy. The thermal and electrical properties of P-PPBP were also investigated. The P-PPBP film containing 40 mol % phosphonic acid groups showed a proton conductivity of about 10 -4 S cm -1 at 90 %R.H.