High synergistic effects of natural-based tea saponin in intumescent flame-retardant coatings for enhancement of flame retardancy and pyrolysis performance

Abstract

Abstract Tea saponin intumescent flame-retardant coatings (TS-IFRCs) is a green and high-efficiency flame-retardant coating based on natural-based tea saponin (TS), and has been confirmed with superior flame retardancy. The present study determined and assessed the effects of TS on the flame-retardant mechanism in composite tea saponin intumescent flame-retardant coatings (CTS-IFRCs) through the analysis of TG-DSC, FT-IR, SEM-EDS and pyrolysis kinetics. It has been demonstrated from the results that TS, synergized with other components in CTS-IFRCs, has direct and significant impacts on the char layer microstructure, flame retardancy and pyrolysis performance, these influences contributed to the double effects of TS as a blowing agent in gas phase flame-retardant mechanism, and as a carbon agent in condensed phase flame-retardant mechanism. High synergistic effects of natural-based TS revealed in this study have provided effective theoretical basis for emerging environmentally friendly bio-based flame-retardant materials and explored a new way for the utilization of TS.