Preparation and properties of epoxy-modified thermosetting phenolic fiber

This article proposes the preparation and microwave thermal cured (MTC) epoxy-modified phenolic fibers for the first time. Epoxy-modified thermoplastic phenolic resin was first prepared in acidic condition using phenol, formaldehyde, and epichlorohydrin as the reactants, and then underwent additive reaction with formaldehyde to obtain epoxy-modified thermosetting phenolic resin, which was converted into nascent fibers through wet spinning. Finally, epoxy-modified phenolic fibers were obtained through different curing methods including solution cured, solution thermal cured, microwave cured, MTC, and was characterized by infrared spectroscopy, microscopic infrared imaging, nuclear magnetic resonance, thermogravimetric analysis, and scanning electron microscopy. The experiment results show that MTC epoxy-modified phenolic fibers have optimal mechanical property with ultimate elongation of 4% and breaking strength of 133 MPa.