Synergistic flame retardant effect of melamine in ethylene–vinyl acetate/layered double hydroxides composites

Mg–Al–Fe ternary layered double hydroxides (LDHs) were synthesized based on Bayer red mud by a calcination–rehydration method, and characterized by X-ray diffraction (XRD) and thermogravimetric analysis (TG). The synergistic effects between melamine and LDHs in ethylene–vinyl acetate (EVA) composites were studied using limiting oxygen index (LOI), UL 94, cone calorimeter test (CCT), smoke density test (SDT), and thermogravimetry–fourier transform infrared spectrometry (TG–IR). Though melamine decreases the LOI values of EVA/LDHs/melamine composites, a suitable amount of melamine can apparently improve UL 94 rating; the composite with 45 % LDHs and 5 % melamine can pass UL 94 test. The CCTs results indicate that heat release rates (HRR) of EVA/LDHs/melamine composites decreased in comparison with that of EVA/LDHs composites. The SDT results show that melamine is helpful to smoke suppression. The TG–IR data show that the ternary composites have a higher thermal stability than that of the binary composites.     

Synergistic effects of zinc oxide with layered double hydroxides in EVA/LDH composites

The synergistic effects of zinc oxide (ZnO) with layered double hydroxides (LDH) in ethylene vinyl acetate copolymer/LDH (EVA/LDH) composites have been studied using thermal analysis (TG), limiting oxygen index (LOI), UL-94 tests, and cone calorimeter test (CCT). The results from the UL-94 tests show that the ZnO can also act as flame retardant synergistic agents in the EVA/LDH composites. The CCT data indicated that the addition of ZnO in EVA/LDH system can greatly reduce the heat release rate. The TG data show that the ZnO can increase the thermal degradation temperature and the charred residues after burning.     

Combustion behavior and thermal stability of ethylene-vinyl acetate composites based on CaCO3-containing oil sludge and carbon black

CaCO₃-containing oil sludge (OS) is a by-product from petroleum industry, with great amount of production. Therefore, an effective processing methods for CaCO₃-containing OS is urgently needed. Herein, ethylene-vinyl acetate (EVA) composites based on CaCO₃-containing OS and carbon black (CB) were prepared by melt blending method. The combustion behavior and thermal stability of flame-retardant EVA/OS/CB composites were investigated by cone calorimeter test, limiting oxygen index (LOI), scanning electron microscopy (SEM), smoke density test (SDT), and thermogravimetry-Fourier infrared spectrometry. The heat release rate and smoke production rate of the ternary composites containing 3% CB significantly decreased compared with the EVA/OS composites and pure EVA. Moreover, addition of a certain amount of CB could evidently increase LOI values. The morphologies and structures of the residues, revealed by SEM, ascertained that a better carbonaceous protective layer was formed on the ternary composites than the EVA/OS composite. It was obtained from SDT that CB in the material could retard the smoke production with the application of the pilot flame. The EVA/OS/CB composites assumed a higher thermal stability than the EVA/OS composites and pure EVA.

     

Synergistic effects of ammonium polyphosphate and red phosphorus with expandable graphite on flammability and thermal properties of HDPE/EVA blends

In this work, the flame‐retardant high‐density polyethylene/ethylene vinyl‐acetate copolymer (HDPE/EVA) composites have been prepared by using expandable graphite (EG) as a flame retardant combined with ammonium polyphosphate (APP) and red phosphorus masterbatch (RPM) as synergists. The synergistic effects of these additives on the flammability behaviors of the filled composites have been investigated by limiting oxygen index, UL‐94 test, cone calorimeter test, thermogravimetric analysis (TGA), Fourier‐transform infrared (FTIR), and scanning electron microscopy. The results show that APP and RPM are good synergists for improving the flame retardancy of EG‐filled HDPE/EVA composites. The data from TGA and FTIR spectra also indicate the synergistic effects of APP and RPM with EG considerably enhance the thermal degradation temperatures but decrease the charred residues of the HDPE/EVA/EG composites because the flame‐retardant mechanism has changed. The morphological observations present positive evidences that the synergistic effects take place in APP and RPM with EG in flame‐retardant EG‐filled HDPE/EVA/EG composites. The formation of stable and compact charred residues promoted by APP and RPM with EG acts as effective heat barriers and thermal insulations, which improves the flame‐retardant performances and prevents the underlying polymer materials from burning. Copyright © 2015 John Wiley & Sons, Ltd.     

Influence of Fe‐MMT on the fire retarding behavior and mechanical property of (ethylene‐vinyl acetate copolymer/magnesium hydroxide) composite

In this work, Fe‐montmorillonite (Fe‐MMT) is synthesized and used as a synergistic agent in ethylene vinyl acetate/magnesium hydroxide (EVA/MH) flame retardant formulations. The synergistic effect of Fe‐MMT with magnesium hydroxide (MH) as the halogen‐free flame retardant for ethylene vinyl acetate (EVA) is studied by thermogravimetric analysis (TGA), limiting the oxygen index (LOI), UL‐94, and cone calorimetry test. Compared with that of Na‐MMT, it indicates that the synergistic effects of Fe‐MMT enhance the LOI value of EVA/MH polymer and improve the thermal stability and reduce the heat release rate (HRR). The structure and morphology of nanocomposites are studied by X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The mechanical properties of the EVA composites have also been studied here, indicating that the use of Fe‐MMT reduces the amount of inorganic fillers. MH hence enhances the mechanical properties of the EVA composite while keeping the UL‐94 V‐0 rating. Copyright © 2008 John Wiley & Sons, Ltd.     

Layered double hydroxides intercalated with borate anions: Fire and thermal properties in ethylene vinyl acetate copolymer

Fire and thermal properties of ethylene vinyl acetate (EVA) composites prepared by melt blending with layered double hydroxides (LDH) have been studied. Two types of LDHs intercalated with borate anion were prepared using the coprecipitation method and the metals Mg²⁺, Zn²⁺ and Al³⁺. Characterization of the LDHs and the EVA composites was performed using X-ray diffraction, thermogravimetric analysis, and cone calorimetry. Thermal analyses show that the addition of LDHs improves the thermal stability of EVA. Fire properties evaluated using the cone calorimeter were significantly improved in the EVA/LDH composites. The peak heat release rate was reduced by about 40% when only 3% by weight of the LDH was added to the copolymer. Comparison of the fire properties of the LDHs with those of aluminum trihydrate (ATH), magnesium hydroxides (MDH), zinc hydroxide (ZH) and their combinations at 40% loading, reveal that the LDHs were more effective than when MDH and ZH are used alone.     

MgAlZnFe-CO3 LDHs对PBS膨胀阻燃体系性能的影响

采用恒定pH值共沉淀法在自制反应器中合成了不同原料配比的碳酸根型镁铝锌铁层状双羟基金属氧化物（MgAlZnFe-CO₃ LDHs）,并通过熔融共混MgAlZnFe-CO₃ LDHs、聚磷酸铵（APP）、三聚氰胺（MA）和全降解材料聚丁二酸丁二醇酯（PBS）制备出PBS膨胀阻燃材料. 采用傅里叶红外光谱（FTIR）、热失重（TG）、X射线衍射（XRD）、扫描电子显微镜（SEM）及元素分析（ICP）对MgAlZnFe-CO₃ LDHs进行了表征,并对PBS膨胀体系进行了力学性能和阻燃性能等测试. 结果表明,当Mg²⁺,Zn²⁺,Al³⁺和Fe³⁺的摩尔比为9：3：3：1时,合成的MgAlZnFe-CO₃ LDHs热稳定性最好,晶态结构规整,呈形貌规则的六边形片状;当MgAlZnFe-CO₃ LDHs的添加质量分数为1%时（阻燃剂的总添加质量分数为20%）时,PBS膨胀阻燃体系的极限氧指数（LOI）达到35%,垂直燃烧测试达到UL-94 V-0级别,力学性能得到较大改善. 实验结果表明,低添加量的MgAlZnFe-CO₃ LDHs与膨胀阻燃剂（IFR）协效阻燃PBS,一方面能够改善膨胀阻燃剂恶化PBS力学性能的现象,另一方面协同效应能够明显提高PBS的阻燃性能.     

The Effect of Hydrotalcite and Zinc Oxide on Smoke Suppression of Commercial Rigid PVC

To reduce the smoke release of poly(vinyl chloride) (PVC) during burning, layered double hydroxides (LDHs) and zinc oxide (ZnO) powders were used to modify the polymer. The results indicated that the addition of LDHs‐ZnO had a significant effect on smoke suppression. The limiting oxygen index (LOI) reached a maximum value and the smoke density rank (SDR) exhibited a minimum value when the weight percentages of LDHs and ZnO in PVC were 3% and 2%, respectively. Thermal stabilities of the modified PVC and degradation products were investigated by means of thermogravimetry and pyrolysis‐gas chromatography‐mass spectra (Py‐GC‐MS). The LDHs‐ZnO obviously accelerated the decomposition of PVC to release hydrogen chloride, and the decomposed PVC consequently produced the trans‐conjugated polyene sequences, which easily formed crosslinked structures. However, a cyclization reaction in PVC chain without the additives produced aromatic compounds such as benzene, toluene, and naphthalene at 350°C. Even though, an amount of aromatic compounds was released from the PVC modified with LDHs‐ZnO at the temperature of 600°C, the content of the decomposed products is relatively lower compared to unmodified PVC.     

Flammability and thermal degradation of flame retarded polypropylene composites containing melamine phosphate and pentaerythritol derivatives

The flammability of polypropylene (PP) composites containing intumescent flame retardant additives, i.e. melamine phosphate (MP) and pentaerythritol (PER), dipentaerythritol (DPER) or tripentaerythritol (TPER) was characterized by limiting oxygen index (LOI), UL 94 and the cone calorimeter, and the thermal degradation of the composites was studied using thermogravimetric analysis (TG) and real time Fourier transform infrared (RTFTIR). It has been found that the PP composite containing only MP does not show good flame retardancy even at 40% additive level. Compared with the PP/MP binary composite, the LOI values of the PP/MP/PER (PP/MP/DPER or PP/MP/TPER) ternary composites at the same additive loading are all increased, and UL 94 ratings of most ternary composites studied are raised to V-0 from no rating (PP/MP). The cone calorimeter results show that the heat release rate and smoke emission of some ternary composites decrease in comparison with the binary composite. It is noted from the TG data that initial decomposition temperatures of ternary composites are lower than that of the binary composite. The RTFTIR study indicates that the PP/IFR composites have higher thermal oxidative stability than the pure PP.     

Preparation of microcapsulated ammonium polyphosphate,pentaerythritol with glycidyl methacrylate,butyl methacrylate and their synergistic flame‐ retardancy for ethylene vinyl acetate copolymer

A new series of microcapsules containing pentaerythritol (PER) and ammonium polyphosphate (APP) with glycidyl methacrylate and butyl methacrylate as shell materials were synthesized by in situ polymerization. The structure and performance of the microencapsulated APP and microencapsulated PER were characterized by Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle. The flame retarded ethylene‐vinyl acetate copolymer (EVA) composites were studied by limiting oxygen index, UL‐94 test, and cone calorimeter. It was found that the microencapsulation of flame retardants (FRs) with the glycidyl methacrylate and butyl methacrylate lead to a decrease in the particle's water solubility and an improvement of the hydrophobicity. Results also demonstrated that the FR properties of EVA/microencapsulated APP/microencapsulated PER composites were better than those of the EVA/APP/PER composites at the same loading of FRs. The thermogravimetric analysis results reflected that the microencapsulated EVA composites had better thermal stability because of the forming of stable char during the combustion. Copyright © 2013 John Wiley & Sons, Ltd.     

Microencapsulated ammonium polyphosphate with urea–melamine–formaldehyde shell: preparation,characterization, and its flame retardance in polypropylene

Microencapsulated ammonium polyphosphate (MCU‐APP) with urea–melamine–formaldehyde (UMF) resin is prepared by in situ polymerization, and is characterized by FTIR and XPS. The microencapsulation of APP with the UMF resin leads to a decrease in the particle's water solubility. The flame retardant actions of MCU‐APP and APP in PP are studied using limiting oxygen index (LOI) and UL‐94 test, and their thermal stability is evaluated by thermogravimetric analysis. It is found that the LOI value of the PP/MCU‐APP composite is higher than the value of the PP/APP composite. In comparison with the PP/MCU‐APP composites, the LOI values of the PP/MCU‐APP/DPER ternary composites at the same additive loading increase, and UL‐94 ratings of most ternary composites are raised to V‐0. The water‐resistant properties of the PP composites containing APP and MCU‐APP are studied. Moreover, the combustion behavior of the PP composites is investigated by the cone calorimeter. Copyright © 2008 John Wiley & Sons, Ltd.     

Effect of Ni cations and microwave hydrothermal treatment on the related properties of layered double hydroxide-ethylene vinyl acetate copolymer composites

The effect of Ni cations and synthetic methods on the crystallinity, morphology, thermal stability and hydrophobic properties of carbonate-containing layered double hydroxides (LDHs) was investigated. The conventional hydrothermal treatment (CHT) and microwave hydrothermal treatment (MHT) methods were used to synthesize LDHs. The microwave treatment LDHs (MgAl-MHT and NiMgAl-MHT) have higher crystallinity and smaller crystal sizes than the conventional hydrothermal treatment LDHs (MgAl-CHT and NiMgAl-CHT). IR results indicate that the interactions of both OH(-)-CO(3)(2-) and CO(3)(2-)-CO(3)(2-) in NiMgAl-MHT are weaker. Furthermore, the thermal decomposition of OH(-) and CO(3)(2-) in the NiMgAl-MHT sample occurred earlier and faster than that of other LDHs. The contact angle values indicate that NiMgAl-MHT has the highest hydrophobicity. The influences of the LDHs on the thermal degradation and flame retardance of ethylene vinyl acetate copolymer (EVA)-LDH composites have also been studied in detail. NiMgAl-MHT has the more homogeneous nano-dispersed layers in EVA matrix. All composites enhance the thermal stability compared with the pure EVA because of the release of H(2)O and CO(2). Flame retardance of NiMgAl-MHT-EVA was obviously higher than that of the pure EVA and other composites.     

Synergistic effect of organophilic Fe-montmorillonite on flammability in polypropylene/intumescent flame retardant system

Polypropylene/intumescent flame retardant/organophilic Fe-montmorillonite (PP/IFR/Fe-OMT) nanocomposites were prepared by melting intercalation. In order to investigate the effect of structural Fe³⁺ in the PP/IFR system, the corresponding PP/IFR and PP/IFR/Na-OMT composites were prepared under the same conditions. The thermo-gravimetric analysis data show that the PP/IFR/Fe-OMT nanocomposites have higher thermal stability than the PP/IFR and PP/IFR/Na-OMT composites. The flame retardant results indicate that the limiting oxygen index values of the nanocomposites with Fe-OMT are basically higher than those of the pure PP and the composites containing IFR or Na-OMT/IFR. And the addition of a suitable amount of Fe-OMT in PP/IFR composites can apparently favor UL94 test, and no dripping phenomenon was found. The cone calorimeter test indicates that the heat release rate (HRR) is significantly reduced by the formation of the nanocomposites, and the HRR of the PP/IFR/Fe-OMT nanocomposites are decreased in comparison with those of the PP/IFR/Na-OMT nanocomposites. It is noteworthy that Fe-OMT is helpful to smoke suppression by smoke density test.     

Effect of Organo‐Modified Nanosepiolite on Fire Behaviors and Mechanical Performance of Polypropylene Composites

The objective of the study was to investigate the effect of the organo‐modified nanosepiolite (ONSep) on improving the fire safety of polypropylene (PP). The composites based on PP, flame retardant master batch (MB‐FR, 25 wt% PP+50 wt% decabromodiphenyl ether (DBDPE)+25% antimony trioxide (ATO)) and ONSep were prepared via melt blending. The results of the limiting oxygen index (LOI) and vertical burning rating (UL‐94) test indicated that PP/40 wt% MB composites had no rating with seriously dripping phenomenon, while the LOI value was only 22.5. However, as 4 wt% ONSep was added in PP/40 wt% MB composites, the composites achieved UL94 V‐0 rating and the LOI value was 24.3. In comparison, PP/50 wt% MB composites could not reach the V‐0 rating either. The TGA results revealed that the addition of ONSep enhanced the thermal stability of the PP/MB‐FR composites. The cone calorimeter results indicated that the heat release rate, average mass loss rate, smoke production rate and smoke temperature of the PP/40 wt% MB‐FR/4 wt% ONSep composites decreased in comparison with those of PP/40 wt% MB‐FR composites. Simultaneously, the Young modulus and impact strength were also much better improved with the increase of ONSep loading. Therefore, the synergistic flame retardancy of ONSep in PP/MB‐FR matrix significantly containing a halogen based flame retardant (DBDPE) significantly improved the fire safety and mechanical properties of the composites, and allowed to decrease the total amount of brominated fire retardants.     

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

The natural basalt fiber (BF) was incorporated into EVA composites with environmental‐friendly nickel alginate‐brucite based flame retardant (NiFR), to further improve the flame‐retardant effect and mechanical properties. The flame retardancy of EVA composites were characterized by LOI, UL 94, and cone test. With 55 wt% loading, 3BF/52NiFR had the highest LOI value of 31.9 vol.% in all fiber reinforced composites and pass UL 94V‐0 ratting. And comparing to 55B composite with untreated brucite, 3BF/52NiFR decreased peak of heat release rate by 47.8%, total heat release by 21.9%, and total smoke production by 35.5% and kept more residue 54.0% during cone test. Moreover, 3BF/52NiFR also enhanced the mechanical properties of composites by better compatibility with EVA matrix. BF/NiFR exert synergistic flame‐retardant effect major in promoting charring effect in condensed phase during combustion. The fire‐resisted and rigid BF into the char layer reinforced the intensity of protective barrier which prolonged the residence time of pyrolysis carbonaceous groups degraded from EVA matrix, resulting in less heat and smoke release.     

Synthesis of heptamolybdate‐intercalated MgAl LDHs and its application in polyurethane elastomer

Heptamolybdate (Mo₇O₂₄^6?) was intercalated in the interlayer space between MgAl‐layered double hydroxides (Mo‐MgAl LDHs) by the hydrothermal and ion exchange method, and then polyurethane elastomer (PUE) based composites were prepared by the prepolymerization method with different amounts of Mo‐MgAl LDHs. X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectra, laser Raman spectroscopy (LRS), and scanning electron microscopy (SEM) were employed to characterize the obtained LDHs. The performance of the PUE/LDHs were evaluated by measuring their thermal gravimetric, heat release rate (HRR), and smoke density (Ds). The results show that PUE/LDH composites exhibit a lower peak heat release rate (pk‐HRR), Ds, and a prolonged combustion time, in comparison with neat PUE. Comparison between NO₃‐MgAl LDHs and Mo‐MgAl LDHs containing composites show that the introduction of Mo⁶⁺ is able to facilitate flame retardance and smoke suppression efficiency, which results mainly from the presence of MoO₃ derived from the decomposition of Mo₇O₂₄^6? intercalated LDHs. Mo‐MgAl LDHs reduce the pk‐HRR of composites by 39% with only 1 wt.% content, and the maximum Ds of composites is reduced to a minimal value of 274 with 10 wt.% Mo‐MgAl LDHs. More importantly, LDHs would improve the mechanical properties at a low content. The experimental results reveal the potential of Mo₇O₂₄^6? intercalated LDHs to improve both the flame retardancy and smoke suppression of PUE. Copyright © 2015 John Wiley & Sons, Ltd.     

Synergistic fire safety improvement between oyster shell powder and ammonium polyphosphate in TPU composites

In this article, oyster shell powder (OSP) was used as fire safety agent with ammonium polyphosphate (APP) in thermoplastic polyurethane (TPU) composites. The synergistic fire safety improvement between OSP and APP was intensively investigated using limiting oxygen index (LOI), UL‐94, smoke density test (SDT), and cone calorimeter test (CCT). There is a good synergistic effect of reducing the fire hazards when OSP was used with APP in TPU. The peak heat release rate (pHRR) of the sample with 2.0‐wt% OSP and 8.0‐wt% APP decreased to 86.8 kW/m² from 175.7 kW/m² of the sample with only 10.0‐wt% APP. The SDT results showed that the luminous flux of sample OSP2/APP8 was up to 28.9% at the end of experiment with flame, which was much higher than that of pure TPU (1.5%). The thermal stability and thermal decomposition of TPU composites were characterized by thermogravimetric analysis/Fourier infrared spectrum analysis (TG‐IR). The result revealed the inert gasses (including CO₂ and water vapor) produced by the reaction between OSP and APP. A char formed on the surface of composites, hindered the flame spread, reduced the release of combustible gas, and restricted the precursor of smoke into combustion zone.     

Synergistic flame‐retardant effect of DOPO‐based derivative and organo‐montmorillonite on glass‐fiber‐reinforced polyamide 6 T

Herein, a bridged 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) derivative (PN‐DOPO) in combination with organ‐montmorillonite (OMMT) was used to improve the flame retardancy and mechanical properties of glass‐fiber‐reinforced polyamide 6 T (GFPA6T). The flame retardancy and thermal stabilities of the cured GFPA6T composites were investigated using limiting oxygen index, vertical burning (UL‐94) test, cone calorimeter test, and thermogravimetric analysis (TGA). The morphological analysis and chemical composition of the char residues after cone calorimeter tests were characterized via scanning electron microscopy and energy dispersive spectrometry. The results indicate that 2 wt% OMMT combined with 13 wt% PN‐DOPO in GFPA6T achieved a V‐0 rating in UL‐94 test. The peak heat release rate and total smoke release remarkably decreased with the incorporation of OMMT as compared to those of GFPA6T/15 wt% PN‐DOPO. The TGA results show that the thermal stability and residual mass of the samples effectively increased with the increase in OMMT content. The morphological analysis and composition structure of the residues demonstrate that a small amount of OMMT could help form a more thermally stable and compact char layer during combustion. Also, with the incorporation of OMMT, the layers consisted of more carbon‐silicon and aluminum phosphate char in the condensed phase. Furthermore, GFPA6T/PN‐DOPO/OMMT composites exhibited excellent mechanical properties in terms of flexural modulus, flexural strength, and impact strength than the GFPA6T/PN‐DOPO system. The combination of PN‐DOPO and OMMT has improved the flame retardancy and smoke suppression of GFPA6T without compromising the mechanical properties.     

Flame retardant epoxy composites with epoxy‐containing polyhedral oligomeric silsesquioxanes

A kind of polyhedral oligomeric silsesquioxanes (POSS) containing the propoxyl‐epoxy and phenyl groups (pr‐ep‐Ph‐POSS) was synthesized via hydrolytic condensation reaction. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy, and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry identified the structure of the pr‐ep‐Ph‐POSS, including major caged Si₆O₉ (T6), Si₁₀O₁₅ (T10), Si₁₂O₁₈ (T12), etc. The pr‐ep‐Ph‐POSS was applied into the epoxy resin to achieve EP/pr‐ep‐Ph‐POSS composites. Thermogravimetric analysis indicated that EP/pr‐ep‐Ph‐POSS showed excellent thermal properties than pure EP. The fire behaviors of EP/pr‐ep‐Ph‐POSS composites were evaluated based on the cone calorimetry, limiting oxygen index (LOI), UL‐94 vertical burning test, and smoke density test. The smoke density decreased by ~30%, the LOI value reached to 26.4%, dripping was inhibited, and the peak of heat release rate decreased by ~62%. X‐ray photoelectron spectroscopy analysis and FTIR indicated that protective‐barrier effect is the main flame‐retardant mode of action for pr‐ep‐Ph‐POSS, due to the formation of the Si‐O‐Si, Si‐O‐C, and Si‐C condensed phase, which improve the thermal stability, strength, and integrity of the char layer.     

Preparation of a novel phosphorus‐containing organosilicon and its effect on the flame retardant and smoke suppression of polyethylene terephthalate

A novel phosphorus‐containing silicone flame retardant (PDPSI) was prepared by Mannish reaction, and a series of PDPSI/PET composites were prepared by melt blending method. The nuclear magnetic resonance (¹H NMR), Fourier transformation infrared (FTIR), and the thermogravimetric analyzer (TGA) results indicated that PDPSI showed network structure and owned good thermal stability, with the char residue of 62.2% at 800°C. The flame retardancy of PDPSI/PET composites was characterized by limiting oxygen index (LOI), vertical burning tests (UL‐94), and cone calorimeter (CCT). The results revealed that the addition amount of PDPSI was 5%, the LOI value of PDPSI/PET composites increased to 27.3%, and UL‐94 test passed V‐0 rating. When the PDPSI loading was 3%, PET composites showed excellent flame retardancy and smoke suppression, with a decrease in the peak heat release rate (PHRR) by 71.19% and the total smoke release (TSP) reduced from 14.4 to 11.1m². The scanning electron microscopy (SEM) and FTIR results of char residue demonstrated that the flame‐retardant mechanism of PDPSI was solid phase flame retardant. PDPSI catalyzed the aromatization reaction of PET to promote the formation of a dense and continuous carbon layer, finally improving the flame retardancy and smoke suppression properties of PET.