Synthesis of a bio‐based piperazine phytate flame retardant for epoxy resin with improved flame retardancy and smoke suppression

Abstract

Piperazine phytate (PIPT), a bio‐based nitrogen‐phosphorus containing flame retardant, was feasibly synthesized by the reaction of piperazine (PI) with phytic acid (PA) in ethanol. The structure and chemical composition of PIPT were systematically characterized by NMR, FTIR, XRD, TEM and EDX. Epoxy resin (EP) composites with PIPT were prepared by utilizing 4, 4′‐diaminodiphenylmethane as a curing agent. The flame retardancy, mechanical performances and thermal decomposition of the EP composites were studied. The results show that the EP composite containing 15 wt% PIPT (sample EP/15PIPT) passes UL‐94 V0 rating with a limiting oxygen index reaching 35.5%. The cone calorimetric tests results demonstrate the peak heat release rate and total smoke release of EP/15PIPT are about 51.4% and 44.9% reduced than which of pure EP, respectively. The morphology of residual char reveals that the EP/ PIPT composites can form good and compact char during the combustion. In comparison with pure EP, the mechanical performances of the EP/PIPT composites decrease slightly as PIPT content increases.

A facile method for synthesis of novel phenyl phosphates flame retardants and their application in epoxy resin

“…The PO 34 associated with 1140 cm −1 appeared in PPOA, PPOP, and DPOA together. Due to the phosphate formation, the peaks of NH and NH 2 were disappeared and the intensity of around 2740 cm −1 peaks matched with OH 24 were significantly reduced compared to PPOA in PPOP and DPOA, respectively 32 …”

“…For EP/PPOP‐3 and EP/DPOA‐3 composites, the T onset were 330.4 and 336.3°C, the T 50% were 336.3 and 414.6°C, which were lower than EP, respectively. The early decomposition of PPOP and DPOA, especially phosphorus‐containing groups, catalyzed degradation and carbonization of EP, 32,40 causing the decrease of T onset . The T max (the temperature at the maximum mass loss) of EP, EP/PPOP‐3, and DPOA‐3 were similar and all samples showed a one‐step decomposing process.…”

Functionalizing mesoporous silica with a nano metal–organic phosphonate towards mechanical‐robust, thermal‐resistant, and fire‐safety epoxy resin

“…The surface ratio of D to G ( I D / I G ) usually reflects the graphitized degrees of the chars. The higher the graphitized degree of the char is, the better physical shielding effect the char performs 52 . The I D / I G value of pure EP is up to 3.10, whereas the values of EP/mSiO 2 @TETP‐1, EP/mSiO 2 @TETP‐3 and EP/mSiO 2 @TETP‐5 decrease to 2.96, 2.72, and 2.49, respectively.…”

In Situ Polymerization and Flame Retardant Mechanism of Bio‐Based Nitrogen and Phosphorus Macromolecular Flame Retardant in Plywood

“…LOI test results are better than other phytic acid based biological flame retardants and other types of biological flame retardants. [ 27–30 ] The flame retardant results could effectively meet the flame retardant requirements. With the further increase of temperature, the flame retardant performance of flame retardant plywood did not further improve, and the LOI value of plywood decreased after the anti‐loss test.…”

“…However, the LOI value of 170 BF-A plywood treated with BF-A decreased to 24.3% after the anti-loss test, which could not meet the flame retardant requirements. At 170 °C, the LOI values of plywood treated with BF-B flame retardant solution before and after the anti-loss test were 42.3% and [27][28][29][30] The flame retardant results could effectively meet the flame retardant requirements. With the further increase of temperature, the flame retardant performance of flame retardant plywood did not further improve, and the LOI value of plywood decreased after the anti-loss test.…”