New polyvinyl chloride (PVC) nanocomposite consisting of aromatic polyamide and chitosan modified ZnO nanoparticles with enhanced thermal stability, low heat release rate and improved mechanical properties

In this paper, zinc magnesium methyl cyclohexylphosphinate double salt (ZnMg (MHP)) was synthesized and used as flame retardant for PA6. The structure and the flammability of ZnMg (MHP) had been studied. The results presented that the LOI of PA6 with 20wt% filler loading improved from 21.2% to 31.4%, and the vertical burning test passed UL94 V-0 rating. TG analyses showed that ZnMg (MHP) had excellent thermal stability. DSC displayed that ZnMg (MHP) melted at 235°C. The tests of flammability revealed that ZnMg (MHP) had a strong inhibition effect on heat release rate (HRR) of the composites.

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Effect of Magnesium Hydroxide and Aluminum Hydroxide on the Thermal Stability, Latent Heat and Flammability Properties of Paraffin/HDPE Phase Change Blends

Polymers ◽

10.3390/polym12010180 ◽

2020 ◽

Vol 12 (1) ◽

pp. 180 ◽

Cited By ~ 4

Author(s):

Ru Zhou ◽

Zhuang Ming ◽

Jiapeng He ◽

Yanming Ding ◽

Juncheng Jiang

Keyword(s):

Thermal Stability ◽

Phase Change ◽

Heat Release ◽

Flame Retardant ◽

Latent Heat ◽

Aluminum Hydroxide ◽

Heat Release Rate ◽

Magnesium Hydroxide ◽

Release Rate ◽

Gravimetric Analysis

In this study, paraffin was selected as the phase change material (PCM) and high-density polyethylene (HDPE) as the supporting material to prepare a flame-retardant PCM system. The system consisted of paraffin, HDPE, expanded graphite (EG), magnesium hydroxide (MH) and aluminum hydroxide (ATH). The thermal stability and flame retardancy were studied by thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM) and cone calorimeter test (CONE). The SEM proved that the addition of MH and ATH can produce an oxide film on the surface of the composite material and form a “physical barrier” with the char layer, generated by the expansion of EG, preventing the transfer of heat and oxygen. The TGA test showed that, compared with other flame-retardant systems, the materials with added MH and ATH have a higher thermal stability and carbonization ability, and the amount of char residue has increased from 17.6% to 32.9%, which reduces the fire risk of the material. The flame retardant effect is obvious. In addition, the addition of MH and ATH has no significant effect on the phase transition temperature and latent heat value of PCMs. The CONE data further confirmed that MH and ATH can work with EG to prevent heat release, reduce the total heat release rate (THR) value and effectively suppress the generation of smoke, CO and CO2. The peak heat release rate (PHRR) value also decreased, from 1570.2 kW/m2 to 655.9 kW/m2.

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Fire Safety Assessment of Epoxy Composites Reinforced by Carbon Fibre and Graphene

Applied Composite Materials ◽

10.1007/s10443-020-09824-4 ◽

2020 ◽

Vol 27 (5) ◽

pp. 619-639 ◽

Cited By ~ 1

Author(s):

Qiangjun Zhang ◽

Yong C Wang ◽

Constantinos Soutis ◽

Colin G. Bailey ◽

Yuan Hu

Keyword(s):

Mechanical Properties ◽

Heat Conduction ◽

Carbon Fibre ◽

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Structural Integrity ◽

Composite Panel ◽

Maximum Temperature ◽

In Fire

Abstract This paper presents a coupled numerical investigation to assess the reaction to fire performance and fire resistance of various types of epoxy resin (ER) based composites. It examines the fire response of carbon fibre (CF) reinforced ER (CF/ER), ER with graphene nanoplatelets (GNP/ER) and CF reinforced GNP/ER (CF/GNP/ER). Thermal, physical and pyrolysis properties are presented to assist numerical modelling that is used to assess the material ability to pass the regulatory vertical burn test for new aircraft structures and estimate in-fire and post-fire residual strength properties. Except for the CF/GNP/ER composite, all other material systems fail the vertical burn test due to continuous burning after removal of the fire source. Carbon fibres are non-combustible and therefore reduce heat release rate of the ER composite. By combining this property with the beneficial barrier effects of graphene platelets, the CF/GNP/ER composite with 1.5 wt% GNP and 50 wt% CF self-extinguishes within 15 s after removal of the burner with a relatively small burn length. Graphene drastically slows down heat conduction and migration of decomposed volatiles to the surface by creating improved char structures. Thus, graphene is allowing the CF/GNP/ER composite panel to pass the regulatory vertical burn test. Due to low heat conduction and reduced heat release rate, the maximum temperatures in the CF/GNP/ER composite are low so the composite material retains very high in-fire and post-fire mechanical properties, maintaining structural integrity. In contrast, temperatures in the CF/ER composite are much higher. At a maximum temperature of 86 °C, the residual in-fire tensile and compressive mechanical strengths of CF/GNP/ER are about 87% and 59% respectively of the ambient temperature values, compared to 70% and 21% respectively for the CF/ER composite that has a temperature of 140 °C at the same time (but the CF/ER temperature will be higher due to continuing burning). Converting mass losses of the composites into char depth, the post-fire mechanical properties of the CF/GNP/ER composite are about 75% of the ambient condition compared to about 68% for the CF/ER composite.

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Preparation of γ-Divinyl-3-Aminopropyltriethoxysilane Modified Lignin and Its Application in Flame Retardant Poly(lactic acid)

Materials ◽

10.3390/ma11091505 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1505 ◽

Cited By ~ 6

Author(s):

Yan Song ◽

Xu Zong ◽

Nan Wang ◽

Ning Yan ◽

Xueying Shan ◽

...

Keyword(s):

Thermal Stability ◽

Lactic Acid ◽

Heat Release ◽

Flame Retardant ◽

Heat Release Rate ◽

Flame Retardancy ◽

Release Rate ◽

Poly Lactic Acid ◽

Modified Lignin ◽

Thermal Stability Of

Lignin can be a candidate as a charring agent applied in halogen-free flame retardant polymers, and incorporation of silicon and nitrogen elements in lignin can benefit to enhancing its thermal stability and charring ability. In the present work, wheat straw alkali lignin (Lig) was modified to incorporate silicon and nitrogen elements by γ-divinyl-3-aminopropyltriethoxysilane, and the modified lignin (CLig) was combined with ammonium polyphosphate (APP) as intumescent flame retardant to be applied in poly(Lactic acid) (PLA). The flame retardancy, combustion behavior and thermal stability of PLA composites were studied by the limited oxygen index (LOI), vertical burning testing (UL-94), cone calorimetry testing (CCT) and thermogravimetric analysis (TGA), respectively. The results showed a significant synergistic effect between CLig and APP in flame retarded PLA (PLA/APP/CLig) occured, and the PLA/APP/CLig had better flame retardancy. CCT data analysis revealed that CLig and APP largely reduced the peak heat release rate (PHRR) and total heat release rate (THR) of PLA, indicating their effectiveness in decreasing the combustion of PLA. TGA results exhibited that APP and CLig improved the thermal stability of PLA at high temperature. The analysis of morphology and structure of residual char indicated that a continuous, compact and intumescent char layer on the material surface formed during firing, and had higher graphitization degree. Mechanical properties data showed that PLA/APP/CLig had higher tensile strength as well as elongation at break.

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Synthesis of new aromatic polyamides containing α-amino phosphonate with high thermal stability and low heat release rate

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-019-08383-6 ◽

2019 ◽

Vol 138 (6) ◽

pp. 3949-3959 ◽

Cited By ~ 2

Author(s):

Mohsen Hajibeygi ◽

Hosein Jafarzadeh ◽

Meisam Shabanian ◽

Henri Vahabi

Keyword(s):

Thermal Stability ◽

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

High Thermal Stability ◽

Aromatic Polyamides ◽

Amino Phosphonate

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Intumescent flame retardant coating for polyamide 6,6 (PA 6,6) fabrics containing carbon nanotubes: Synergistic effect of filler on thermal stability and flame retardancy

Textile Research Journal ◽

10.1177/0040517518783355 ◽

2018 ◽

Vol 89 (10) ◽

pp. 2031-2040 ◽

Cited By ~ 4

Author(s):

Fanglong Zhu ◽

QQ Feng ◽

YF Xu ◽

JF Hu

Keyword(s):

Carbon Nanotubes ◽

Thermal Stability ◽

Heat Release ◽

Flame Retardant ◽

Heat Release Rate ◽

Flame Retardancy ◽

Release Rate ◽

Intumescent Flame Retardant ◽

Flame Resistance ◽

Limiting Oxygen Index

Flame retardant mixtures of multi-walled carbon nanotubes (MWCNTs) and intumescent flame retardant (IFR) coatings were applied to polyamide 6,6 (PA 6,6) fabrics to explore whether MWCNTs acted as a good synergist on the thermal stability and flame resistance of the IFR system. The influence of MWCNTs on the flame retardant properties and thermal degradation of the PA 6,6 fabrics were investigated by limiting oxygen index (LOI), vertical burning test (VBT), thermogravimetric analyzer (TGA), scanning electron microscopy (SEM) and cone calorimeter test (CCT). The peak heat release rate and total heat release of the IFR-PA 6,6 fabric with three kinds of wt% MWCNTs were lower than those of the only traditional IFR-PA 6,6 fabric (reduced by 74.2–76.4% and 74.3–76.5%, respectively). As compared to the traditional IFR coating, it was found that no enhancements for thermal stability and flame retardancy in terms of the ability to retard ignition were achieved for the MWCNT/IFR coating. These results demonstrated that the introduction of MWCNTs into an IFR coating can improve the flame retardancy of PA 6,6 fabric in terms of the heat release rate from CCT analysis, but it failed other burning measurements, such as LOI and VBT.

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Effect of Synthesized Chitosan Flame Retardant On Flammability, Thermal, And Mechanical Properties of Vinyl Ester/Bamboo Nonwoven Fiber Composites

10.21203/rs.3.rs-723535/v1 ◽

2021 ◽

Author(s):

Prabhakar M.N. ◽

K Venkata Chalapathi ◽

Ur Rehman Shah Atta ◽

Jung-il Song

Keyword(s):

Mechanical Properties ◽

Heat Release ◽

Flame Retardant ◽

Heat Release Rate ◽

Release Rate ◽

Vinyl Ester ◽

Natural Fiber ◽

Fiber Composite ◽

Thermal And Mechanical Properties ◽

Ul 94

Abstract In this study, chitosan-based bio-flame retardant additive (referred to as NCS) was prepared by altering the chitosan (CS) chemically with silica (S) via ion interchange reaction and studied the effect on flame retardant, thermal and mechanical properties of vinyl ester/bamboo fiber (VE/BF) composites manufactured by the vacuum assisted resin transfer molding (VARTM) process. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis used to characterize the NCS. The spectral results revealed a new peak at 1560 cm-1 corresponding to NH3+–-O Si, bring up the interactive bond between CS and S. SEM, and XRD showed the diverse morphology (coarse surface), and significant decrement in the intensity of diffraction patterns respectively support further the formation of NCS. The heat release rate of NCS decreased significantly by 76%, and residual char increased by 47% compared with chitosan. The flame retardant and thermal behavior of NCS-VE/BF composites were examined by UL-94 standards, micro and cone calorimeter and thermogravimetric analysis. The results showed a delay in burning time in UL-94, enhanced LOI % and decrement of peak heat release rate and total heat release rate compared to pure composites by 32, 14, and 18%, respectively. The residual char increased by 47%. The mechanical properties also improved satisfactorily. Overall, the synthesized NCS could be suitable for the fabrication of sustainable flame-retardant natural fiber composite without deterioration of mechanical properties that are suitable for sub-structural parts in engineering applications.

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