Synthesis of poly(m‐phenyleneisophthalamide) by solid‐state polycondensation of isophthalic acid with m‐phenylenediamine

The synthesis of poly(m-phenyleneisophthalamide) was performed by thermal solid-phase polymerization from isophthalic acid and m-phenylenediamine without using any solvents or condensation agents. The two-stage heating process was conducted. The oligo(m-phenyleneisophthalamide) was first synthesized at a relatively low temperature (260 °C for 1 h), followed by the polycondensation at 400 °C for 1 min under reduced pressure to produce the aramid with an inherent viscosity of 0.55 dL/g.