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In this work, a phosphorous-containing flame retardant, phenylphosphonate-based compound (EHPP), is synthesized by alcoholysis and hydrazinolysis of phenylphosphonic dichloride, which is subsequently introduced to ethylene-vinyl-acetate (EVA) copolymer to improve its flame retardant performance. The resultant compound was characterized by Fourier transform infrared (FTIR), 1H NMR, 13C NMR, and 31P NMR. The influence of the EHPP on the combustion behaviors of EVA is studied by limiting oxygen index (LOI), UL-94, and cone calorimeter test. The results show that 1 wt% EHPP can reduce peak heat release rate (PHRR) by 40%. Moreover, 2 wt% EHPP can increase LOI from 20.5% to 25.5%. Thermogravimetric analysis/infrared spectrometry (TGA-FTIR) was used to detect the gaseous products of EVA/EHPP to study the gaseous-phase flame retardant mechanism. The EHPP released phosphorus-containing radicals to capture highly active free radicals to improve the flame retardancy of EVA.

Inspired by the significant catalytic charring effect of metal–organic frameworks (MOFs), Cu‐MOF decorated ammonium polyphosphate (APP@Cu‐MOF) was prepared by coupling agents to improve the fire safety of epoxy resin (EP). After adding 9 wt% APP@Cu‐MOF, the fire performance of EP is significantly improved with limiting oxide index (LOI) value of 29.4 and UL‐94 V‐0 rating. The peak heat release rate (PHRR), total smoke production (TSP), CO production, and CO2 production of EP composite samples decreased by 34.6%, 54.7%, 24.6% and 30.0%, respectively. It is proposed that the synergistic effect among Cu‐MOF and APP promoted the char formation of EP. The dense carbon layers formed a barrier that prevented the transfer of heat and inhibited the release of toxic gases, thus acting as a flame retardant. This work provides a new strategy to develop a high‐efficient MOF‐decorated flame retardant with smoke inhibition, toxicity reduction, and catalytic carbonization effect. [ABSTRACT FROM AUTHOR]

For the purpose of promoting mechanical properties of bisphenol‐A polycarbonate (PC) reinforced by rigid organic styrene–acrylonitrile copolymer (SAN) particles, styrene/acrylonitrile/glycidyl methacrylate terpolymer (SAG) was synthesized and applied as compatibilizer for PC/SAN blends. It is found that the phase morphology of PC/SAN/SAG blends is closely related with their mechanical properties. Large continuously distributed SAN phase or spherical dispersed SAN particles with average diameter over 2 μm tend to trigger premature tensile failure of blends due to stress concentration. The incorporation of SAG can simultaneously reinforce and toughen PC/SAN blends by controlling the size and distribution of the dispersed SAN particles. For the blends with fixed PC/SAN ratio, the elongation at break and fracture energy are markedly improved when SAN domain size is reduced by adding appropriate amount of SAG. Typically, for blends with a PC/SAN ratio of 75/25, adding 3 wt% SAG will cause the average diameter of SAN particles to reduce from 2.35 ± 1.20 to 0.74 ± 0.25 μm, meanwhile up to 95% increment in elongation at break and 115% increment in fracture energy is achieved. [ABSTRACT FROM AUTHOR]

Lanthanum phenylphosphonate (LaHPP) was synthesized through solution reflux method with a hydrothermal reaction. The synergistic effect of decabromodiphenyl oxide (DBDPO) and LaHPP on thermal stability and flame retardancy of polycarbonate (PC) were investigated. Transmission electron microscope graphs showed that LaHPP dispersed well in the PC matrix. Thermogravimetric analyses indicated that the addition of LaHPP into PC/DBDPO composites led to better thermal stability. An appropriate content (1 wt%) of LaHPP could improve the UL94 rating (from V‐2 to V‐0) and limiting oxygen index value (from 32.8 to 40.5%) dramatically, and also brought an effective reduction in peak heat release rate and smoke release rate in cone calorimeter. Investigation of gaseous pyrolysis products and char residues demonstrated that LaHPP promoted the formation of more compact and solid chars, which acted as physical barriers to inhibit heat and oxygen transfer. The inside char layers also provided more space and time for DBDPO to play its flame retardant role in gaseous phases. POLYM. COMPOS., 40:986–999, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT Graphene nanoplatelets (GNPs) with the char barrier effect were combined with brominated polystyrene (BPS) and antimony trioxide (Sb2O3) to improve the flame retardancy and thermal stability of high-density polyethylene. Thermogravimetric analysis, limited oxygen index (LOI) testing, and vertical burning testing (UL-94) showed that the presence of GNPs led to enhanced thermal oxidation stability and significantly reduced the flammability. The addition of 1 wt % GNPs to polyethylene/BPS-Sb (mass ratio = 92/6/2) led to UL-94 grades from NG (first burning time > 30 s) to V-2 (total burning time = 14 s), and the LOI value increased from 23.4 to 24.1%. The results of the pyrolysis products provided evidence that the GNPs restricted volatilization. The morphology of the chars also proved the formation of the char layer, which could act as a barrier to isolate the material from the flame and retard the vaporization of flammable gases via a tortuous pathway. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40520. [ABSTRACT FROM AUTHOR]

Brominated flame-retardant high-densitypolyethylene (HDPE) compositescontaining graphene nanoplatelets (GNPs) were prepared via melt blending.A Lewis acid catalyst, aluminum chloride (AlCl3), was adoptedto initiate the Friedel–Crafts reaction, which contributedto the good dispersion of GNPs and improvement of interfacial interaction.Scanning electron microscopy (SEM) showed that the size of GNPs decreasedand the dispersive state of GNPs was improved with the addition ofAlCl3. The maximum decomposition temperature (Tmax), modulus, and viscosity increased as the catalystcontent increased, whereas the peak heat release rate (PHRR) and thetotal heat release (THR) decreased with increasing catalyst content.However, gel permeation chromatography (GPC) verified the degradationfor HDPE at high catalyst concentration, and then thermal oxidationstability and flame retardancy worsen. The variety of performanceof the composites was the result of the competition between improvingthe dispersion and degradation of composites. [ABSTRACT FROM AUTHOR]

A lamellar cerium phenylphosphonate (CeHPP) was synthetized through reflux method and it was combined with decabromodiphenyl oxide (DBDPO) to prepare flame retarded poly(ethylene terephthalate) (PET) nanocomposites. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) showed that CeHPP was a one-dimensional nanocrystal with the interlamellar distance of 1.57 nm. Thermogravimetric analysis (TGA) indicated that CeHPP had the excellent thermal stability and abundant char residue. Transmission electron micrographs (TEM) revealed that CeHPP dispersed homogenously in both PET and DBDPO phases. CeHPP could form a continuous and compact char layer in PET nanocomposites and had a synergistic effect with DBDPO. The collaboration of 2 wt% CeHPP and 6 wt% DBDPO dramatically improved UL 94 rating (from V-2 to V-0) and limiting oxygen index (LOI) value (from 22.9% to 29.1%) for PET. What is more, the mechanical properties were evaluated by tensile tests. POLYM. COMPOS., 35:539-547, 2014. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

At present, the application of fullerene in polymer materials has become an attractive issue. Fullerene can enhance the thermal and flame‐retardant properties of polymers due to its high capacity to trap free radicals. Fullerene also has good synergistic effect with inorganic metal flame retardant, intumescent flame retardant, brominated flame retardant (BFR), clay, carbon nanotubes, graphene oxide, and so on. In this review, the impact and mechanism of fullerene and its derivatives on the thermal and flame‐retardant properties of polymeric materials are discussed. And the prospect of fullerene in flame‐retardant polymer composites is also briefly introduced by analyzing the research progress in the recent years. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 47538. [ABSTRACT FROM AUTHOR]