High-Temperature Auto-Cross-Linking Cyclotriphosphaznene: Synthesis and Application in Flame Retardance and Antidripping Poly(ethylene terephthalate)

Abstract

A novel phenylethynyl-terminated cyclotriphosphazene oligoimides (hexakis (4-phenyl acetylene imide phenoxy) cyclotriphosphazene, HPAIPC) was synthesized to solve the conflict between flame retardance and antidripping of poly­(ethylene terephthalate) (PET). The PET/HPAIPC composites were prepared by direct melt compounding, and the flame-retardancy and antidripping properties of the composites were investigated. The results revealed that thermal stability, self-extinguishing ability, and inhibition of melt-dripping properties of PET/HPAIPC composites were obviously enhanced by the introduction of high-temperature auto-cross-linking cyclo­tri­phosphazene oligomides into polyester. All results of rheological analyses, pyrolysis products, and the morphology of the char demonstrated that the HPAIPC could exhibit a greater complex viscosity and enhance the physical barrier effect retarding the flammable gases, heat flux, and flame.

Flame‐retardant poly (ethylene terephthalate) enabled by a novel melamine polyphosphate nanowire

“…As could be seen from Figure , the FT‐IR spectra of PET/FR5.0 nanocomposite were similar to that of pure PET. Several characteristic gaseous products such as benzoic acid (1760 cm −1 ), carbon dioxide (2360 cm −1 ), and aromatic compounds (1510 cm −1 ) with strong intensities were detected clearly . The benzoic acid and aromatic compounds released from PET were highly combustible and could release a great amount of heat in the burning process.…”

Effect of trisilanolphenyl‐POSS on rheological, mechanical, and flame‐retardant properties of poly(ethylene terephthalate)/cyclotriphosphazene systems

“…However, the sample PET/4%PACP/1%T‐POSS, when the frequency was less than 0.1 rad s −1 , was an elastic solid rather than a viscous fluid because G < G ′, as shown in Figure . This result illustrated the strong association between the PET matrix and the combination of fillers 4%PACP and 1%T‐POSS …”

“…For the PET/5%PACP composite, the viscosity value was higher than that of the neat PET in all frequency regions. This was attributed to the unstable hydroxyl groups of PACP, and they played the role of a crosslinking catalyzer during processing, leading to branching and hence resulting in increased entanglement of the polymer chains . Meanwhile, the dynamic viscosity of the polymer also increased after the addition of T‐POSS; the complex viscosity of PET/1%T‐POSS was higher (11.9 Pa s) than that of neat PET (8.4 Pa s) at a frequency of 1 rad s −1 , due to the silicon hydroxyl of T‐POSS acted as crosslinking catalyzer as well …”

Synergistic effects of a novel silicon‐containing triazine charring agent on the flame‐retardant properties of poly(ethylene terephthalate)/hexakis (4‐phenoxy)cyclotriphosphazene composites

“…The crystallinity of PET composites increased, for instance, ᭝X PET/10%IFR was 36.4%, which was higher than that of pure PET (27.0%). Those implied that PNCP and TSCA acted as a kind of heterogeneous nucleation agent, leading to the strengthen of PET crystallinity [25,32,41]. The chain segments of PET tended to arrangement more order, more physical network structures and increased the entanglement.…”