Kinetic study of copolymerized PMIA with ether moiety under air pyrolysis

Copolymerized poly(m-phenylene isophthalamide) (co-PMIA) was synthesized by solution polycondensation using m-phenylenediamine and isophthaloyl dichloride and 3,4′-oxydianiline (3,4′-ODA). This paper described the preparation and characterization of the copolymers from various contents 3,4′-ODA to afford co-PMIA with ideal high molecular mass. The copolymer showed excellent thermal stability with the glass transition temperature of 267 °C and the onset decomposition temperature (5% mass loss) of 445 °C. The thermal degradation of co-PMIA was measured with various thermal analytical techniques; the pyrolysis products were obtained and analyzed under air atmosphere. The possible thermal decomposition mechanism of co-PMIA was discussed. The present pyrolysis was investigated using TG under air atmosphere at four different heating rates (5–20 °C min⁻¹). Three different kinetic methods, the iso-conversional Ozawa–Flynn–Wall and Kissinger and Crane methods were applied on TG data of co-PMIA to calculate the kinetic parameters including activation energy, pre-exponential factor and reaction order.