A highly efficient gas-dominated and water-resistant flame retardant for non-charring polypropylene

Abstract

Traditional phosphorus-nitrogen (P-N) flame-retardant systems for polypropylene (PP) always act through joint action of the gaseous phase and condensed phase, and are accompanied with a decrease of the thermal stability and water resistance. In this work, a novel mono-component and gas-dominated flame retardant, named DPPIP, was prepared through an amidation reaction of diphenylphosphinyl chloride and piperazine, and used to flame retard PP. Experimental results confirmed that both the thermal stability and water resistance of PP/DPPIP were improved. The initial thermal decomposition temperature of PP/25 wt% DPPIP at 5 wt% weight loss was 287.5 C under air atmosphere, which is higher than that of neat PP (266.1 C). Besides, a water-resistance test verified that PP/25 wt% DPPIP had a weight loss of only about 0.52 wt%. More importantly, the flame retardant ability of PP/25 wt% DPPIP had been greatly improved, passing the V-0 rating (UL-94). Furthermore, after the water-resistance test, the LOI value of PP/25 wt% DPPIP exhibited nearly no difference and still passed the UL-94 V-0 rating. A cone calorimeter (CC) result indicated that DPPIP had a positive effect on inhibiting heat release of PP during combustion. All of these combustion tests displayed that there was no char left. The flame retardant mechanism of DPPIP was investigated with py-GC/MS and TG-FTIR. The results illustrated that the gaseous phase resulting from the thermal decomposition of DPPIP played the leading role in the self-extinguishing behavior of PP/DPPIP, which consisted of a large amount of inflammable gaseous products such as piperazine and its derivatives, and phosphorus-containing structures.

Fully Bio-Based Phytic Acid–Basic Amino Acid Salt for Flame-Retardant Polypropylene

“…With further increasing the content of PaArg, the PP/PaArg 22 , PP/PaArg 25 , and PP/PaArg 30 samples may achieve the UL-94 V-0 rating and their LOI values further increase to 26.0, 27.0, and 28.5%, respectively. Clearly, PaArg has an excellent flame retarding effect on PP, and its efficiency is also superior to most of traditional typical halogen-free flame retardants such as DPPIP, PETBP, and so forth. − For PaLys-filled PP, when the content of PaLys increases to 25 wt %, PP/PaLys 25 may pass the UL-94 V-0 rating. In the vertical burning test, PaLys shows a lower flame-retardant efficiency than PaArg, but it still has a higher flame-retardant efficiency than some traditional flame retardants such as MAPP and ethanolamine–APP .…”

Flame Retardant Polypropylenes: A Review

“…Symbols are indicative of different types of nitrogen flame retardant used. Here: ■ MP-40 [ 63 ], MPPK-15, MPPK-20, MPPK-25 [ 64 ], MTP-15, MTP-20, MTP-25, MTP-30, m-MTP-30 [ 65 ], MPyP-30 [ 57 ], MPyP-30, TA-CFA-30 [ 66 ], TA-CFA-30 [ 39 ], TA-CFA-30 [ 40 ], TA-CFA-25 [ 37 ], TA-CFA-25 [ 32 ], TA-CA-ZnO-25 [ 29 ], TA-CA-25 [ 67 ], TA-CA-20 [ 27 ], TA-CA-20 [ 23 ], TA-IFR-20 [ 68 ], TA-IFR-25 [ 31 ], PI-FR-25 [ 69 ], PI-IFR-30 [ 70 ], PI-IFR-20, PI-IFR-30, PI-IFR-40 [ 71 ], NOR116-0.5 [ 72 ], NOR116-0.3 [ 73 ], PPU-CA-25 [ 50 ], N-FR-22, N-FR-25 [ 74 ], N-IFR-5, N-IFR-10, N-IFR-15, N-IFR-20, N-IFR-25 [ 75 ], N-IFR-25 [ 76 ], PN-IFR-30 [ 56 ].…”

“…Overall, like what happened to other polymers [77,78], combinatorial flame retardants may be the solution to flammability reduction of PP materials. [65], MPyP-30 [57], MPyP-30, TA-CFA-30 [66], TA-CFA-30 [39], TA-CFA-30 [40], TA-CFA-25 [37], TA-CFA-25 [32], TA-CA-ZnO-25 [29], TA-CA-25 [67], TA-CA-20 [27], TA-CA-20 [23], TA-IFR-20 [68], TA-IFR-25 [31], PI-FR-25 [69], PI-IFR-30 [70], PI-IFR-20, PI-IFR-30, PI-IFR-40 [71], NOR116-0.5 [72], NOR116-0.3 [73], PPU-CA-25 [50], N-FR-22, N-FR-25 [74], N-IFR-5, N-IFR-10, N-IFR-15, N-IFR-20, N-IFR-25 [75], N-IFR-25 [76], PN-IFR-30 [56].…”

Fire Retardancy of Poly(ethylene 2,5-furandicarboxylate-co-ethylene terephthalate) Regulated by Phosphinate

“…In addition, there is another phosphonate prepared using the reactions between diphenylphosphinic chloride (DPCl) and phenolic hydroxyl groups . It is found that diphenyl phosphinate groups are more likely to function in the gas phase. − A flame retardant (DPOD) was derived from DPCl and daidzein and was applied in EP. A UL-94 V-0 level and a LOI of 34.7% were obtained for the composites with 6 wt % DPOD.…”