Wet-Spinning Preparation of High-Performance Phenol-Modified Melamine-Formaldehyde Fibers

In order to improve the toughness of melamine formaldehyde (MF) fibers, the modified fibers with varying synthesis mole ratios were fabricated through wet spinning utilizing melamine and paraformaldehyde as the primary constituents and phenol as the modifying agent. The structural characteristics and properties of the fibers were assessed and examined through Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and mechanical property evaluations. The results showed that the incorporation of phenol led to a significant enhancement in both the thermal stability and mechanical properties of the fibers. Specifically, when the mole ratio of melamine, phenol, and paraformaldehyde was 1:1:4 and the heat curing temperature was 180 °C, the fiber exhibited a breaking strength of 151 MPa and an elongation at break of 15.1%. This represented an increase in elongation at break of approximately 84% compared to the unmodified fiber without phenol. Furthermore, the thermal properties of the modified fibers were notably improved, as evidenced by an increase in char yield at 700 °C from 27.7% to 62.5%.