DOPO‐based curing flame retardant of epoxy composite material for char formation and intumescent flame retardance

Abstract

Phosphorus-containing flame retardant (HBAEA-DOPO) for epoxy resin was synthesized by addition reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) with bis[2-(4-hydroxybenzylideneamino) ethyl]amine (HBAEA) that was synthesized via 4-hydroxybenzaldehyde with diethylenetriamine. HBAEA-DOPO was mixed with 4,4 0-diaminodiphenyl sulfone to co-cure the epoxy resin of diglycidyl ether bisphenol A. The silane modified nano-silica (nano-SiO 2) was used to reinforce the epoxy resin. Thermal stability and dynamic mechanical properties of the cured epoxy materials were studied with the use of thermogravimetric analysis and dynamic mechanical thermal analysis. Flame retardance and burning behavior were evaluated by the limiting oxygen index (LOI), vertical burning test, and the cone calorimetry. The cured epoxy materials have excellent thermal stability, and the temperatures at the maximum weight loss rate are over 384.0 C. The characteristic temperature corresponding to 5.00 wt% of thermal decomposition reaches 341.5 C as 1.00 wt% of phosphorus content is loaded. Flame retardant grade meets the V-0 level. The fire residue mass gradually increases with HBAEA-DOPO and nano-SiO 2. The characteristics of high flame retardance and smoke suppression of HBAEA-DOPO and nano-SiO 2 on the cured epoxy composites have been demonstrated to be related to char formation and intumescent flame retardance in the condensed phase.

Synthesis of a Novel Flame Retardant Containing Phosphorus, Nitrogen, and Silicon and Its Application in Epoxy Resin

“…As summarized in Table , The TTI value of EP/TDA-5 thermoset was lower than that of pure EP thermoset, which is in accordance with the T 5% results as discussed above. The reason is that the catalytic decomposition effect of TDA weakened the ignition resistance of EP thermosets. − …”

A new‐type terephthalonitrile derivative flame retardant of bi‐DOPO compound with hydroxyl and amino groups on epoxy resin

“…The phosphorus in DEZ had a different chemical environment due to chiral carbon and steric effect. 23…”

Preparation of melamine borate coated red phosphorus microcapsules and use of zinc borate as synergistic flame retardant in polyethylene

“…[4][5][6][7][8] In recent years, halogen-free flame retardants have attracted significant attention from researchers due to their excellent characteristics such as low toxicity, low smoke, environmental-friendly, and they burned without the generation of halogenated fumes. [9][10][11][12][13] Halogen-free flame retardants mainly include phosphorus, nitrogen, boron and metal hydroxide. [14][15][16][17][18][19][20] Red phosphorus (RP) is a common and practical inorganic flame retardant due to its high efficiency, and phosphorous content as well as low cost.…”