Constructing a Fully Biobased Coating to Improve the Flame Retardancy, Antibacterial Properties, and UV Resistance of Polyamide 6 Fabrics

• Published in: ACS applied engineering materials Vol. 1; no. 1; pp. 268 - 277
• Main Authors: Liu, Jian, Qiu, Shuang, Qi, Peng, Sun, Jun, Li, Hongfei, Gu, Xiaoyu, Zhang, Sheng
• Format: Journal Article
• Language: English
• Published: American Chemical Society 27.01.2023
• Subjects: flammability; biobased; PA6 fabrics; antidripping; multifunction
• ISSN: 2771-9545; 2771-9545
• DOI: 10.1021/acsaenm.2c00061

A fully biobased solvent-free coating composed of tannic acid (TA) and taurine (TN) was constructed and introduced on polyamide 6 (PA6) fabric by a dipping-nipping process to improve the flame retardancy, antibacterial properties, and UV resistance of the fabric. Fire behavior characterization indicated that the presence of the TN/TA coating eliminated the melt dripping of the PA6 fabric and increased the limiting oxygen index to 26.8% from 19.4% of the control fabric sample. The total heat release and total smoke production of the coated fabric sample was reduced by 31.3% and 66.7%, respectively, compared to that of the control fabric sample. Moreover, the antibacterial activity of the coated fabric against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus was significantly enhanced. After 120 h of UV irradiation, the warp and weft tensile strength of the TN/TA coated PA6 fabric sample were increased by 200.9% and 159.0%, respectively, compared to that of the control PA6 fabric sample; in addition, the LOI and the damage length of the TN/TA coated PA6 fabric were almost unaffected. It was demonstrated that TA promoted the char formation and eliminated the melt dripping in the condensed phase, and TN diluted O2 and combustible volatiles by releasing incombustible SO2 in the gas phase. This work has provided useful information to prepare fully biobased multifunctional coatings for PA6 synthetic fabrics.