Optimization of mechanical, thermal, and ignition properties of polyester fabric using urea and phosphoric acid

This research aimed to improve anti-dripping and ignitability properties of polyester fabric polyethylene terephthalate (PET) by using urea (CO(NH2)2), phosphoric acid (H3PO4), methyltrimethoxysilane (MTMS) via sol-gel technique. Methyl groups served as blocking groups preventing oxygen from penetrating into PET specimen, so the fire stopped. The interaction between the coating and irradiated surface of PET was detected by Fourier-transform infrared spectroscopy using UV/ozone for different time periods. The mechanical properties (tensile and elongation %) of the specimens were tested according to ISO 13934. The thermogravimetric analysis, derivative thermogravimetric analysis, and differential scanning calorimetry proved that the new coating has a direct efficiency to protect the PET fabric from ignition. Different standard test methods, ISO 4589, ASTM D635, and EN ISO 1716, were used to investigate the ignition properties of untreated and treated specimens. The results showed that the coated specimens with a urea solution only as a first layer, and then the sol solution as the second layer have the highest flame retardant effect compared to the other methods. This results in improving the dripping and ignition properties of a polyester fabric.