Study on flame retardancy and smoke suppression of PET by the synergy between Fe₂O₃ and new phosphorus-containing silicone flame retardant

Abstract

To reduce the environmental hazard from the flame retardant, a halogen-free phosphorus-containing silicone flame-retardant poly N, N dimethylene phosphate aminopropyl siloxane (PDPSI) was prepared following the Mannich reaction. Then, PDPSI and ferric oxide (Fe2O3) were used for the preparation of synergistic flame-retardant polyethylene terephthalate (PET). The flame-retardant test results revealed that at 2% PDPSI/Fe2O3 content and 1:2 mass ratio of PDPSI to Fe2O3, the limit oxygen index value of the PDPSI/Fe2O3/PET composite material was 27.9%, reaching the flame-retardant level and passing the V-0 rating in the UL-94 test. In addition, the PDPSI/Fe2O3/PET composites had a char residue content of 17.5% at 700°C, an increase of 30.6% compared to that of the pristine PET. In the cone calorimeter test, the addition of PDPSI/Fe2O3 significantly reduced the peak heat release rate (PHRR), total heat release (THR) rate, and total smoke production (TSP) value of the resulting PET composites. PHRR and THR decreased by 66.05% and 14.3%, respectively. The TSP value decreased from 14.4 m2 to 8.1 m2, a decrease of 43.8%. The scanning electron microscopy images and Fourier-transform infrared spectra of the char residue showed a significant synergy between Fe2O3 and PDPSI, changing the structure of the carbon layer in continuous and dense form, thus the flame retardancy and smoke suppression of the PET composites improved. In addition, the tensile strength of the PET composite was 42.11 MPa, which was only 1.84% less than that of the pristine PET.

Glass fiber reinforced PET modified by few‐layer black phosphorus

“…Compared with PET/GF, new bands at 1040 (P–OH), and 877 cm −1 (OP–O) could be observed in the FTIR spectrum of PET/GF@RP‐2.7 residues. Bands at 1241 (PO), 1084 (P–O–C), 960 (P–O–Ph), and 877 (OP–O) 29–31 cm −1 were detected in the FTIR spectrum of PET/GF@BP‐2.7 residues. The appearance of these bands suggests the existence of various phosphorus‐containing compound in the char residue.…”

A smartDOPO‐containing decoration armed on Salen‐polyphosphazene toward high‐efficient flame retardancy for epoxy thermoset

“…[ 46–49 ] The chemical bonds in the residue of DK@Salen‐PZN‐Ni/EP composite imply the existence of oxides as well as the formation of some complex substances derived from the interaction between DK and Salen‐PZN‐Ni (e.g., SiOP and SiP), representing that DK modification on enhancing charring formation and retarding fire spread in condensed phase depend on combustible chemical reaction as well as their physical barrier effect. [ 50 ] However, these specific combustion products in residue are still ambiguous known. A reasonable deduction on these possible substances in residue after combustion is in favor of understanding the flame retardant process.…”

3D Printing and Solvent Dissolution Recycling of Polylactide–Lunar Regolith Composites by Material Extrusion Approach

“…The T 5% values of the PLA/CLRS-1 composites decreased from 328 • C to 290 • C with the addition of 5 wt.% CLRS-1. The further addition of CLRS-1 up to 10 wt.% led to a lower T 5% of 279 • C, which was associated with the catalysis effect of the metal oxide and phosphate in the CLRS-1 lunar regolith simulant [37][38][39]. With the addition of CLRS-1, the T max values of the PLA/CLRS-1 composites also shifted to low temperatures.…”