Facile preparation of ladder-like polyphenyl silsesquioxanes-sodium benzenesulfonate micro-nano compound with novel pyrolysis model and high flame retardancy for epoxy resin

To reduce the fire hazard of epoxy resin and expand its application scenarios, a novel micro-nano compound of ladder-like polyhedral oligomeric silsesquioxane (PPSQ) and sodium benzenesulfonate (BSNa) was successfully developed. Due to the addition of BSNa, the thermal decomposition behaviour of ladder-like PPSQ was completely changed, making it an effective additive to improve the flame retardancy of epoxy resin. Compared with neat epoxy resin, at 3wt% addition, the peak of heat release rate(p-HRR), the peak of carbonic oxide production rate(p-COP), the peak of smoke production rate(p-SPR) and the peak of carbon dioxide production rate(p-CO₂P) were reduced significantly. In addition, the mechanism of the negative influence of PPSQ-BSNa on the flame retardancy of epoxy resin at excessive addition was detailed and analyzed in this work. Finally, this work provides a new prospect and strategy of synthesis metal containing POSS to reduce the fire hazards of epoxy resin.