Abstract
Synthesis, characterization and thermal properties of some rigid epoxy polymers cured from aromatic mono- and di-amine are presented. The aromatic mono- and diamine are prepared via nucleophilic substitution reaction of p-nitrochlorobenzene with the respective mono- and dihydroxybiphenyl, and via subsequent hydrogenation of the aromatic nitro products. The structures of both, mono- and di-amines, are confirmed by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance ((HNMR)-H-1) and elemental (CHN) analysis. Furthermore, three types of rigid epoxy polymers, (i) HBREP, (ii) HCREP, and (iii) BCREP, are prepared by melt processing and curing of the epoxy monomers with (i) monoamine, (ii) diamine, and (iii) 1: 1 mixture of mono-and di-amines, respectively. These rigid epoxy polymers are characterized by FTIR spectroscopy, X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). TGA and DSC results show excellent thermal oxidative stability (T-d10 >= 400 degrees C) and substantially high glass transition temperatures (T-g=80-120 degrees C) for these rigid epoxy polymers. The intermediary BCREP exhibits the highest T-g as well as the maximum heat resistance and thermal stability regardless of its lower chemical crosslink density with respect to HCREP. The kinetic analyses of the oxidative degradation of polymers also reveal sufficiently high activation energy of pyrolysis for BCREP.