In this work, we present the synthesis of a new epoxy resin based on phosphorus trichloride and ethylene dianiline. The obtained epoxy resin is crosslinked thermally by methylene dianiline (MDA) and deposited on carbon steel. The structural microscopic characterization was conformed using the Fourier Transform Infrared Spectroscopy (FTIR)and Nuclear Magnetic Resonance (NMR) and macroscopy by X-ray diffraction (XRD). The viscosimetric behavior was performed using the capillary viscometer type UBBELOHDE.