Synergistic Fire Retardancy of Bis(1‐methoxy‐2,2,6,6‐tetramethylpiperidin‐4‐yl)sebacate and Tris(2,4,6‐tribromophenoxy)‐1,3,5‐triazine/Sb₂O₃ in HIPS

Abstract

Bis(1-methoxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (NORSM) was found to perform an exceptional synergistic effect with tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBPC)/Sb2O3 in HIPS. The LOI of fire retardant HIPS (FR-HIPS) with 16 wt% of TTBPC/Sb2O3 increased from 23.8% to 25.2%, the flame retardant rating of FR-HIPS was improved from UL 94 V-2 to UL 94 V-0, and various heat release parameters such as peak heat release rate, total heat release, and mean effective heat of combustion were greatly lowered by combining NORSM of 0.50 wt%. The Py-GC/MS results revealed that NORSM induced the role of synergistic effect; the main mechanisms were as follows: the active radicals such as methoxy radicals and aminyl radicals produced by the pyrolysis of NORSM promote the release of bromine radicals from TTBPC and the formation of HBr and CO2, which improves the flame retardancy of TTBPC/Sb2O3; the above active radicals, together with HBr, quench active free radicals, such as the hydroxyl radical (OH), and decompose the free radical source, which interrupts the chain reaction during combustion and results in a more efficient flame retardant effect in gaseous phase.

Synergistic flame retardancy of bis(1‐methoxy‐2,2,6,6‐tetramethylpiperidin‐4‐yl)sebacate and aluminium hypophosphite/melamine hydrobromide in PP

“…The above‐mentioned analysis of the pyrolysis products shows that NORSM imparts the synergistic effect mainly through the following mechanisms: active radicals such as methyl radicals, methoxy radicals, nitro radicals and aminyl radicals produced by the pyrolysis of NORSM, 20 but methoxy radicals and aminyl radicals might be the most important species for interrupting the free radical reactions during the polymer combustion process, 36 together with PH 3 and HBr, quench active free radical such as hydroxyl radical (·OH), thus the chain reaction of combustion is interrupted, which results in more highly efficient flame retardant effect in gaseous phase 37,38 . However, it has been well established that alkoxy radicals can promote chain scission of polypropylene, 39 thereby accelerating the breakdown of polypropylene during combustion, 19 which is beneficial to burning of PP.…”

“…Furthermore, all materials were used as received. NORSM was prepared according to the process described in the literature 29 …”

“…Charla, et al found that Tinuvin NOR123 exhibited a good synergistic flame retardant effect with brominated phosphate in PP fiber, which had passed the FMVSS 302 test when the concentrations of Tinuvin NOR123 and brominated phosphate were 1 wt% and 2 wt%, respectively 28 . Wu, et al found that bis(1‐methoxy‐2,2,6,6‐tetramethylpiperidin‐4‐yl)sebacate (NORSM) performed an exceptional synergistic flame retardant effect with tris(2,4,6‐tribromophenoxy)‐1,3,5‐triazine/Sb 2 O 3 in high impact polystyrene 29 . Nevertheless, studies elucidating the flame retardancy and the synergistic effect of NORSs are sparse, and the synergistic effect with ALHP/MHB in PP has not been reported at all so far.…”

“…1‐methyloxy‐4‐(dodecyl‐2‐enyl)‐2,2,6,6‐tetramethylpiperidine (NOMe) exhibited exceptional performance and very significant synergistic effect with brominated flame retardants 8 . Wu, et al found that tris(1‐methoxy‐2,2,6,6‐tetramethylpiperidin‐4‐yl) phosphite performed an exceptional synergistic flame retardant effect with tris(2,4,6‐tribromophenoxy)‐1,3,5‐triazine/Sb 2 O 3 in high impact polystyrene 20 . Moreover, some other NORs were also reported in literatures 8,21‐23 …”

Fire‐retardant synergy of tris(1‐methoxy‐2,2,6,6‐tetramethyl‐4‐piperidinyl)phosphite and aluminum hypophosphite/melamine hydrobromide in polypropylene

“…[14] It was also found that bis(1-methoxy-2,2,6,6-tetramethyl-4piperidinyl)sebacate performed an exceptional fire retardant synergy with tri(tribromophenyl) cyanurate/Sb 2 O 3 in high impact polystyrene. [15] In addition, NORSs have some merits such as simple molecular structure and preparation process as well as good heat resistance and anti-migration ability. [16][17][18][19] Some other NORs also exhibit good fire retardancy in PP.…”