Synergistic effect between solid wastes and intumescent flame retardant on flammability and smoke suppression of thermoplastic polyurethane composites

Abstract

Phosphorus tailings and fly ash both are solid wastes and do harm to the environment. Here, they were added into thermoplastic polyurethane (TPU) matrices together with intumescent flame retardants (IFR), and the synergistic effects between IFR and phosphorus tailings or fly ash for improving the flame retardancy of TPU were investigated. The cone calorimeter test (CCT) results indicated that adding phosphorus tailings or fly ash substitute for part of IFR could obtain a better flame retardant effect. The peak heart release rate (PHRR) of TPU/25 wt% IFR composites exhibited a reduction of 77% than that of neat TPU, and the total smoke production presented a reduction of 16%. However, the PHRR value and total smoke production of the sample TPU/20 wt% IFR/5 wt% phosphorus tailings were reduced by 91% and 57%, respectively, compared to that of neat TPU. The dense char promoted by the presence of IFR and phosphorus tailings or fly ash delayed the diffusion of volatile pyrolysis products and transmission of heat and oxygen to the underlying material. Therefore, a certain amount of phosphorus tailings or fly ash can be used as synergistic agents with IFR to enhance the fire safety of TPU materials. From another aspect, it also provides a promising way for recycling use of phosphorus tailings and fly ash.

Construction of Charring-Functional Polyheptanazine towards Improvements in Flame Retardants of Polyurethane

“…Research on P-containing flame retardants is increasing due to environmental pollution caused by halogenated flame retardants [ 13 , 14 ]. A variety of halogen-free flame retardants for polymers have been developed, most of which contain P [ 15 , 16 , 17 , 18 ]. In recent years, phosphorus-doped polyheptazines have attracted increasing attention due to their applications in wastewater treatment [ 19 ], photocatalysts [ 20 , 21 ], electrocatalysts [ 22 ], organic matter degradation [ 23 , 24 ], and bioimaging [ 25 ].…”

Facile preparation and flame retardancy mechanism of cyclophosphazene derivatives for highly flame‐retardant silicone rubber composites

“…As one of the widely‐utilized intumescent flame retardants, organophosphorus molecules are effective radical scavengers, which can quench active free‐radicals effectively 21–23 . Therefore, the synthesis of novel highly efficient phosphorus‐based flame retardants has aroused the concern from scientists and engineers.…”

“…As one of the widely-utilized intumescent flame retardants, organophosphorus molecules are effective radical scavengers, which can quench active free-radicals effectively. [21][22][23] Therefore, the synthesis of novel highly efficient phosphorusbased flame retardants has aroused the concern from scientists and engineers. Cyclotriphosphazenes are inorganic heterocyclic compounds with the general formula of N 3 P 3 R 6 , [24][25][26] where R bonded to phosphorus as an organic group or chlorine atom.…”

Functionalized ZrP nanosheet with free‐radical quenching capability and its synergism in intumescent flame‐retardant polypropylene

“…Over the years, various types of flame retardants have been introduced to reduce flammability of PP. Intumescent flame retardant (IFR), as a potential alternative of halogen flame retardant, has been developed rapidly due to their environment friendly and low smoke . However, there are still many shortcomings of present IFR systems, especially for their low flame‐retardant efficiency.…”