Fully bio-based flame retardant and antibacterial coating for polyethylene terephthalate fabric

In this work, a fully bio-based multi-functional intumescent flame retardant coating containing epsilon-polylysine (epsilon-PL), 5-hydroxymethylfurfural (5-HMF), and phytic acid (PA) was successfully constructed on the polyethylene terephthalate (PET) fabrics via a facile one-pot dip-pad-dry process. The introduction of the coating significantly improved the fire performance of the fabric. The treated PET fabric had a limiting oxygen index value of 28.1 %, and was free of molten drops in the vertical flammable test. The flame retardant mechanism analysis indicated that the three components in flame retardant coating formed intact char layers during combustion which hindered the transfer of oxygen/heat and inhibited the generation of flammable volatiles. The treated PET fabric also exhibited better antibacterial ability against E. coli and S.aureus compared to the control sample. Besides, the breaking strength and the elongation at the break of the treated PET fabric were slightly improved. This work provides a facile and sustainable strategy to fabricate PET fabrics with flame retardancy and anti-dripping properties.