Flame-retardant and antibacterial flexible polyurethane foams with high resilience based on a P/N/Si-containing system

In this work, the coatings used phosphorylated chitosan (PCS) and GP-108 via the dip-coating method presented exceptional flame retardancy and antibacterial properties for flexible polyurethane foams (FPUF). PCS/GP@FPUF with 35% weight gain of PCS/GP can receive the UL-94 V-0 rating and obtain a 32% reduction of peak heat release rate value compared with that of FPUF, and it remains relatively dense char residues. The effective heat of combustion of PCS/GP@FPUF is 21.6 kJ/g, presenting a 22% decrease compared with that of FPUF. Meanwhile, the PCS/GP coatings mainly have the condensed-phase flameretardant mechanism associated with the analysis of char residues and the volatile products released through the thermal degradation process. X-ray photoelectron spectroscopy results confirm that the char residues of PCS/GP@FPUF consist of highly-graphitized carbon and it formed P-N-Si synergistic char layers. In addition, the antibacterial rates of PCS/GP@FPUF against Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) are 99.99%, and the incorporation of GP-108 does not influence the antibacterial properties of PCS. Importantly, the resiliency of FPUFs has been slightly influenced. Briefly, the flame-retardant and antibacterial FPUFs with wonderful resiliency are hopeful to be applied as filler materials for vehicle seats and obtain longer service lives. (c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.