Bis(1-propyloxy-2,2,6,6-tetramethylpiperidin-4-yl)-diazene – An innovative multifunctional radical generator providing flame retardancy to polypropylene even after extended artificial weathering

Design and Utilization of Nitrogen Containing Flame Retardants Based on N-Alkoxyamines, Azoalkanes and Related Compounds

“…This was done by combining the diazene and N-alkoxyamine chemistries into a new molecule, i.e. bis(1-propyloxy-2,2,6,6-tetramethylpiperidyl)-4-diazene (AZONOR) containing both of the favorable constituents [54]. Polypropylene samples containing very low concentrations of 0.25e1 wt% of this additive successfully passed not only the fire standard tests of DIN 4102 B2 and NF P92-505 but also the more challenging UL94 VTM-2 standard.…”

Synthesis of a novel macromolecular charring agent with free-radical quenching capability and its synergism in flame retardant polypropylene

“…It could be seen that the pyrolysis products of PP were a series olefins (1, 2, 3, 4, 5, 7 and 8) and a few alkanes (6), indicating that PP decomposed mainly by bscission [22]. However, for PP/HAPN/APP-2, the most pyrolysis products were polyenes (10, 11, 12 and 13) and there were a few hindered amine derivatives (14), which were generated from the decomposition of HAPN and had a free-radical quenching capability [23]. We could surmise that the hindered amine group and its derivatives could suppress the b-scission of PP through the freeradical quenching reaction, making it generate polyenes rather than olefins and alkanes.…”

(Photo)oxidative Stabilization of Flame-Retarded Polymers

“…These alkoxyamine flame retardants can be used alone [39] or in combinations with other flame retardants [40e43]. Figure 3); very low concentrations (0.5%) provide flame retardancy to polyolefin films even after extended weathering time [45,46]. in phosphorus-containing alkoxyamines [44].…”