Flame retardant and thermal decomposition mechanism of poly(butylene terephthalate)/DOPO‐HQ composites

Abstract

Poly(butylene terephthalate) (PBT)/10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-HQ) composites with poly(ethylene-butylacrylate-glycidylmethacrylate) (PTW) as a compatibilizer were prepared by the twin-screw extruder. The flame retardant and thermal decomposition mechanism of the PBT/DOPO-HQ flame retardant composites was investigated. The limiting oxygen index (LOI), vertical burning test (UL94), cone calorimetric test, thermogravimetric analysis, laser micro-Raman spectrometer (LRS), thermogravimetric analysis-Fourier transform infrared spectrometer, and TG-differential scanning calorimetry of the PBT/DOPO-HQ flame retardant composites were carried out. The LOI results showed that the LOI value PBT/ DOPO-HQ flame retardant composites with PTW compatibilizer is higher than PBT/DOPO-HQ flame retardant composites without PTW compatibilizer. The PBT/PTW/ DOPO-HQ (20%) flame retardant composites achieved UL-94 V-0 classification, but only addition of 20% DOO-HQ to PBT just achieved vertical burning test (UL94) V-2 classification with serious flammable dripping. What's more, the mechanical properties of PBT/DOPO-HQ flame retardant composites were studied. POLYM. COMPOS., 00:000-000,

Novel sustainable biobased flame retardant from functionalized vegetable oil for enhanced flame retardancy of engineering plastic

“…He et al . reported a drastic reduction in tensile strength and Izod impact strength when PBT was added with commercial FR 10-(2, 5-dihydroxyl phenyl)-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-HQ) 49 . They found that the DOPO-HQ required 15 wt% in the PBT in order to achieve V-2 fire class and 20 wt% to reach V-0.…”

“…They found that the DOPO-HQ required 15 wt% in the PBT in order to achieve V-2 fire class and 20 wt% to reach V-0. The tensile strength of PBT reduced ~39% from 56.9 to 34.2 MPa with the addition of 20 wt% DOPO-HQ 49 . This study’s biobased FR required only 7.5 wt% to be effective and showed only a ~13% reduction in tensile strength, which is superior to commercial phosphorus-based FRs in the market in terms of mechanical properties retention.…”

Preparation and Characterization of Flame-Retarded Poly(butylene terephthalate)/Poly(ethylene terephthalate) Blends: Effect of Content and Type of Flame Retardant

“…The remaining N content in the TAD6EG6 was 0.14% N per 1% TAD, which is slightly lower than that of TAD12 (0.16% N per 1% TAD). According to the previous research work [24,29,37,38], the flame-retardant effect of TAD was due to its decomposition products during combustion: (i) P-containing free radicals which can quench the free radicals from degraded resin matrix, and terminate the chain reaction in the gas phase, and (ii) incombustible N-containing gas which diluted the flammable gases released from the resin matrix. TAD acts weak in the condensed phase due to that most of the phosphorus is released to the gas phase, and only minor charring activity is remained [30].…”

Flame retardant and mechanical properties of core‐shell‐like polybutylene terephthalate/intumescent flame retardant through controlling injection time

“…Meanwhile, the infrared spectra of the composites before and after combustion are shown in Figure 7B. After normalization, the peak at 2348 cm −1 corresponded to the CO 2 stretching vibration 17 . A new peak appeared at 1347 cm −1 that was attributed to the stretching vibration of the primary amide C–N generated after burning.…”