Fire hazard suppression of intumescent flame retardant polypropylene based on a novel Ni‐containing char‐forming agent

Abstract

Reducing the fire hazard of polypropylene (PP) is an important research direction in the fields of fire safety materials. In this article, a novel Ni‐containing char‐forming agent (TTPN) was successfully synthesized, using tris(2‐hydroxyethyl) isocyanurate (THEIC), terephthalic acid, and nickel dihydrogen phosphate. Then, TTPN was combined with the silica‐gel microencapsulated ammonium polyphosphate (OS‐MCAPP) to prepare intumescent flame retardant PP composites. From the results of the limiting oxygen index (LOI) test and cone calorimeter, the composite containing 30% IFR (OS‐MCAPP: TTPN = 3:2) shows the highest LOI value of 33.5%, and its peak heat release rate is 275.5 kWm−2, decreased by 79.0% and 37.4% than those of pure PP and the composite containing the char‐forming agent without Ni. Meanwhile, the composite containing TTPN present the best smoke and CO2/CO suppression. The results indicate that TTPN has an excellent ability to dramatically reduce the fire hazard of PP.

Synthesis of a novel char‐forming agent (PEIC): Improvement in flame retardancy, thermal stability, and smoke suppression for intumescent flame‐retardant polypropylene composites

“…Figure (a,b) shows the 1H and the 31P spectrum of PEIC, respectively. In 1H spectra, the peaks showed in the range from δ = 3.5 to 3.6 is due to the H from ─CH 2 ─ in spirocyclic pentaerythritol of PEPA . The signals showed at region “a” and “b,” which are presented in Figure (a), belong to the H atoms in the structure of THEIC .…”

“…From Figure (a), PEIC presents the lowest thermal stability, while the OS‐MCAPP shows the best. The first mitigatory degradation stages of PEIC, under 350 °C, are mainly due to the loss of intermolecular water or other unstable groups . In the temperature range from 350 to 450 °C, because of the thermal decomposition of THEIC in the structure, PEIC shows its second weight loss process .…”

“…The first mitigatory degradation stages of PEIC, under 350 °C, are mainly due to the loss of intermolecular water or other unstable groups . In the temperature range from 350 to 450 °C, because of the thermal decomposition of THEIC in the structure, PEIC shows its second weight loss process . At the temperature 450 °C, the volatilization of further products starts and lasts to 800 °C.…”

Effect of natural basalt fiber for EVA composites with nickel alginate‐brucite based flame retardant on improving fire safety and mechanical properties

“…Recently, layer‐by‐layer assembly for fabricating FRs has been considered feasible, which can deposit multifunctional modifier onto FR particles . Among these agents, silane coupling agents for improving compatibility and transition metals for promoting charring effect have been widely concerned . In our past studies, several metal alginates and silane coupling agents have been layer‐by‐layer deposited onto brucite particles, which enhanced both charring effect and the interfacial interaction with polymers .…”

“…[12][13][14] Among these agents, silane coupling agents for improving compatibility and transition metals for promoting charring effect have been widely concerned. [15][16][17][18][19] In our past studies, several metal alginates and silane coupling agents have been layer-by-layer deposited onto brucite particles, which enhanced both charring effect and the interfacial interaction with polymers. 7,12 Among these FRs, the nickel alginate-brucite based NiFR exerted highest efficiency in promoting charring when used in EVA composites.…”