scholarly journals Decomposition and Flammability of Polyimide Graphene Composites

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 168
Author(s):  
Caroline Akinyi ◽  
Jimmy Longun ◽  
Siqi Chen ◽  
Jude O. Iroh
Keyword(s):  
Thermal Stability ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Analysis Data ◽  
Condensation Polymerization ◽  
Limiting Oxygen Index ◽  
Thermally Stable Polymers ◽  
Decomposition Behavior ◽  
Polyimide Nanocomposite

Polyimide-graphene composites were synthesized by in-situ condensation polymerization and the thermal stability and decomposition behavior of the composites were studied. Polyimides, because of their aromatic backbone, are a class of fire-retardant polymers. Their high char retention ≥50% at testing temperatures ≥600 °C makes them thermally stable polymers. The effect of nanographene sheets on the decomposition behavior of polyimide is presented in this paper. It is shown that the reinforcement of polyimide with nanographene sheets significantly decreased the rate of decomposition of polyimide and increased the char retention of the composite. Thermogravimetric analysis data were used to assess the thermal stability, rate of mass loss and predicted limiting oxygen index of the neat polyimide and composites. Results obtained showed around a 43% decrease in the rate of polyimide degradation at 50 wt.% graphene loading. The limiting oxygen index of the polyimide nanocomposite was calculated by using the char retention, and it was found to increase by up to 24% at 50 wt.% graphene loading over that for the neat matrix.

Preparation and Properties of Recycled-Polyester Nanocomposite Fibers Synergistic Modified with Phosphorus Containing Flame-Retardant and α-Zirconium Phosphate

2014 ◽  
Vol 789 ◽  
pp. 174-177 ◽  
Author(s):  
Zhi Hao Wu ◽  
Li Li Li ◽  
Shuai Shuai Jiang ◽  
Ze Xu Hu ◽  
Yu Chen Mao ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Melt Spinning ◽  
Zirconium Phosphate ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Limiting Oxygen Index ◽  
Phosphorus Containing ◽  
Fire Retardant Properties ◽  
Nanocomposite Fibers ◽  
Positive Effect

Recycled-polyester (RPET) was melt blended with the phosphorus-containing flame retardant (FRP) and α-zirconium phosphate (α-ZrP). The thermal properties of RPET/FRP/α-ZrP composites were analyzed. Modified RPET fibers were prepared through melt spinning of dried RPET nanocomposite chips. The mechanical properties and fire-retardant properties of RPET/FRP/α-ZrP fibers containing different α-ZrP contents were tested. The results show that the synergism of α-ZrP and FRP exerts a positive effect on the mechanical and the flame-retardant property of RPET, leading to nanocomposite fibers of 1.9cN/dtex and 31.6% limiting oxygen index (LOI) value.

Synthesis of a Flame Retardant and Hydrophobic Epoxy Resin with Multiple Elements Synergistic Effect for Tunnel Seepage Prevention Application

2020 ◽  
Vol 842 ◽  
pp. 314-325
Author(s):  
Bin Lin
Keyword(s):  
Flame Retardant ◽  
Epoxy Resin ◽  
Flame Retardancy ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Practical Application ◽  
Water Contact ◽  
Limiting Oxygen Index ◽  
New Perspective ◽  
Grouting Materials

Epoxy resin (EP) mortar usually used to repair the cracking of concrete structure under damp environment, but EP is extremely flammable, thus it’s extremely imperative to design a novel multifunction EP grouting materials with flame retardancy and waterproofness for the practical application. Targeting ingenious decoration of EP grouting materials, multiple flame retardant elements (phosphorus, nitrogen and fluorine) are concurrently introduced into a fire retardant and the fire retardant defined as DDM-FNP. The obtained DDM-FNP/EP grouting composite possess high thermal stability, flame retardancy and hydrophobicity. The limiting oxygen index (LOI) value of DDM-FNP/EP composites has a significant improve, which is increased from 26.7 (EP-0) to 35.8 (EP-4). Composites with more than 10 wt% of DDM-FNP could pass UL-94 V-0 rating without dripping. Compared with EP-0, the PHRR and THR of EP-4 are decreased by 31.1% and 21.6%, respectively. In addition, due to the introduction of the F element, the water contact angle of EP composites is changed from 75.2° (hydrophilicity) to 98.6° (hydrophobicity) after the introduction of a certain amount of DDM-FNP flame retardant. Therefore, this work provide a new perspective to design a multifunction EP grouting composite and improve the value of practical application on seepage prevention of tunnel.

Enhancement of thermal stability and energy storage capability of flexible Ag nanodot/polyimide nanocomposite films via in situ synthesis

2020 ◽  
Vol 8 (36) ◽  
pp. 12607-12614 ◽  
Author(s):  
Shuang Xing ◽  
Zhongbin Pan ◽  
Xiaofeng Wu ◽  
Hanxi Chen ◽  
Xujiao Lv ◽  
...  
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Filler Content ◽  
Composite Films ◽  
In Situ Synthesis ◽  
Nanocomposite Films ◽  
Discharge Energy ◽  
Polyimide Nanocomposite ◽  
Discharge Energy Density

Composite films with an ultralow filler content of 0.1 vol% Ag-NDs exhibit an excellent high-temperature discharge energy density of 2.56 J cm−3, together with efficiency exceeding 80% at a temperature of 150 °C.

Thermal Degradation and Fire Retrandancy of Wood Impregnated with Nitrogen Phosphorus Flame Retardant

2014 ◽  
Vol 931-932 ◽  
pp. 152-156 ◽  
Author(s):  
Atchariyaphorn Phromsaen ◽  
Prinya Chindaprasirt ◽  
Salim Hiziroglu ◽  
Pornnapa Kasemsiri
Keyword(s):  
Weight Loss ◽  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Thermal Degradation ◽  
Degradation Rate ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Limiting Oxygen Index ◽  
Running Water ◽  
Nitrogen Phosphorus

In this research, the effect of diammoniumphosphate (DAP) as fire retardant additive during thermal degradation of wood samples from shorea obtuse (Dipterocarpaceae) has been investigated. Thermal properties of wood samples impregnated with DAP ranging from 0-40 %wt were characterized by thermogravimetric analysis (TGA) and limiting oxygen index (LOI). Leachability of DAP from impregnated samples kept under running water was also investigated. The results indicated that the rate of weight loss obtained from TGA reveal that impregnation of DAP reduced the degradation rate from 0.95%/°C to 0.56%/°C. Furthermore, LOI of woods specimens trended to be increase from 24.8 to 30.6 when they were treated with DAP having a range of 0-30 %wt. Based on the results of this study, wood samples impregnated with 30%wt of DAP can be classified as self-extinguishing materials and cloud meet the requirement for non-flammability in construction. The leachability test indicated that only trace amount of unreacted DAP leached from the samples.

scholarly journals Effects of chemical pre-treatment on structure and property of polyacrylonitrile based pre-oxidized fibers

2020 ◽  
Vol 15 ◽  
pp. 155892501989894
Author(s):  
Xiaolu Sun ◽  
Jiayin Song ◽  
Jin Zhang ◽  
Jingyan Liu ◽  
Huizhen Ke ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Heat Release ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Energy Dispersive Spectrometer ◽  
Chemical Compositions ◽  
Limiting Oxygen Index ◽  
X Ray ◽  
Pre Treatment

Polyacrylonitrile-based pre-oxidized fibers with improved thermal stability, flame retardant, and mechanical properties were made from the pristine polyacrylonitrile fibers through chemical pretreatment followed by pre-oxidation in air. The morphological structure of the polyacrylonitrile-based pre-oxidized fibers was investigated by Fourier transfer infrared spectra, X-ray diffraction, scanning electron microscopy, and X-ray energy dispersive spectrometer. The changes of characteristic functional groups and chemical compositions confirmed the successful modification of the polyacrylonitrile fibers during pre-treatment. The grooves and cracks on the surface of polyacrylonitrile-based pre-oxidized fibers were remarkably decreased in comparison with that of pristine polyacrylonitrile fibers. The evolution of crystalline structure of the polyacrylonitrile fibers proved the occurrence of cyclization reactions during pre-oxidation. Meanwhile, thermal stability, flame retardant, and mechanical properties of polyacrylonitrile-based pre-oxidized fibers were also investigated by thermogravimetric analyzer, oxygen index meter, micro combustion calorimeter, and single fiber tensile tester, respectively. The results demonstrated that the polyacrylonitrile-based pre-oxidized fibers initially pre-treated by hydroxylamine hydrochloride, followed by monoethanolamine, had a high limiting oxygen index of 40.1 and breaking strength of 2.03 cN/dtex. The peak of heat release rate and total heat release of polyacrylonitrile-based pre-oxidized fibers decreased significantly while its charred residues increased, contributing to the improved flame retardant property.

Preparation of dual-functionalized graphene oxide for the improvement of the thermal stability and flame-retardant properties of polysiloxane foam

2018 ◽  
Vol 42 (16) ◽  
pp. 13873-13883 ◽  
Author(s):  
Tianlu Xu ◽  
Chunling Zhang ◽  
Peihong Li ◽  
Xueyan Dai ◽  
Lijie Qu ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Graphene Oxide ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Functionalized Graphene ◽  
Foam Material ◽  
Functionalized Graphene Oxide ◽  
Limiting Oxygen Index ◽  
Flame Retardant Properties ◽  
Combustible Materials

Polysiloxane foam (PSF) is a foam material with outstanding performance. However, the limiting oxygen index (LOI) of pure PSF is only 22.0 vol%, which can be attributed to combustible materials.

scholarly journals Synergistic Effect of APP and TBC Fire-Retardants on the Physico-Mechanical Properties of Strandboard

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 435
Author(s):  
Feiyu Tian ◽  
Deliang Xu ◽  
Xinwu Xu
Keyword(s):  
Mechanical Properties ◽  
Flame Retardants ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Modulus Of Rupture ◽  
Fire Retardancy ◽  
Thickness Swelling ◽  
Cone Calorimetry ◽  
Limiting Oxygen Index ◽  
Polymeric Diphenylmethane Diisocyanate

This study explored the feasibility of fabricating fire-retardant strandboard with low mechanical properties deterioration to the physico-mechanical properties. A hybrid fire-retardant system of ammonium polyphosphate (APP) and 1,3,5-tris(2,3-dibromopropyl)-1,3,5-triazinane-2,4,6-trione (TBC) was investigated. Thermogravimetric analysis results show that both APP and TBC enhance the thermal stability and incombustibility of wood strands. An infrared spectrum was applied to investigate the effect of flame retardants on the curing behaviors of polymeric diphenylmethane diisocyanate (PMDI) resin. Based on the results of limiting oxygen index (LOI) and Cone calorimetry (CONE), APP and TBC both lead to a higher fire retardancy to strandboard. It is worth mentioning that the two flame retardants lead to evidently differential influences on the modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), and water-soaking thickness swelling (TS) properties of strandboard. Hence, a hybrid flame retardant is prominent in manufacturing strandboard with both good fire retardant and satisfying physico-mechanical properties.

scholarly journals Flame Retardant Waterborne Polyurethanes: Synthesis, Characterization, and Evaluation of Different Properties

2021 ◽  
Vol 12 (3) ◽  
pp. 3198-3214
Keyword(s):  
Thermal Stability ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Oxygen Index ◽  
Polymeric Chain ◽  
Resonance Spectroscopy ◽  
Mixing Process ◽  
Polyester Polyol ◽  
Limiting Oxygen Index ◽  
Waterborne Polyurethanes

A series of flame retardant waterborne polyurethanes (WBPUs) with varying NCO:OH mole ratio, i.e., isocyanate:hydroxyl groups, was synthesized using phosphorus-based polyester polyol and isophorone diisocyanate (IPDI). The phosphorus moiety was kept in the polymeric chain, which improves flame retardancy of the WBPU films. The prepolymer mixing process was adopted for the synthesis route of WBPU systems. The presence of structural-functional groups was confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The thermal stability and percentage char yield were observed by TGA analysis. As a consequence of the existence of phosphorous moiety, these WBPUs also exhibit flame retardancy, which was examined by limiting oxygen index (LOI) and UL-94 test. All the samples show an increment in thermal stability with an increase in NCO:OH ratio. Maximum flame retardancy was obtained in FWP5 and FWP6 systems with LOI value of 32%.

scholarly journals Preparation and Synergistic Effect of Chitosan/Sodium Phytate/MgO Nanoparticle Fire-Retardant Coatings on Wood Substrate through Layer-By-Layer Self-Assembly

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 848 ◽  
Author(s):  
Feiyue Zhao ◽  
Tingli Tang ◽  
Sijie Hou ◽  
Yanchun Fu
Keyword(s):  
Self Assembly ◽  
Energy Dispersive Spectrometry ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Layer By Layer ◽  
Wood Substrate ◽  
Limiting Oxygen Index ◽  
Mgo Nanoparticles ◽  
Sodium Phytate ◽  
Mgo Nanoparticle

Fire-retardant chitosan/sodium phytate/MgO nanoparticle (CH/SP/nano-MgO) coatings were loaded on a wood substrate via electrostatic layer-by-layer self-assembly and characterized by scanning electron microscopy and energy-dispersive spectrometry. The flammability and thermal degradation of the original wood and wood samples treated with chitosan, chitosan/sodium phytate, chitosan/sodium phytate/MgO nanoparticles were studied by limiting oxygen index (LOI), exposure combustion experiments and thermogravimetric analysis (TGA), respectively. The CH/SP/nano-MgO coating served as an intumescent fire-retardant system that created a physical protection cover and exhibited the best fire retardant performance. The LOI value was 30.2% and required approximately 16–17 s to self-extinguish when exposed to air. The TGA curves also showed that char formation protected the wood from combustion.

Coating of lightweight wool fabric with nano clay for fire retardancy

2019 ◽  
Vol 110 (5) ◽  
pp. 764-770 ◽  
Author(s):  
Seiko Jose ◽  
Nachimuthu Shanmugam ◽  
Sekhar Das ◽  
Ajay Kumar ◽  
Pintu Pandit
Keyword(s):  
Oxygen Index ◽  
Fire Retardant ◽  
Wool Fabric ◽  
Limiting Oxygen Index ◽  
Analytical Instruments ◽  
Flammability Test ◽  
Nano Clay ◽  
Fire Retardant Properties ◽  
In Fire

Nano-kaolinite was applied to lightweight wool fabric for imparting fire retardant finish using pad batch as well as exhaust method. The effect of fire retardant treatments on the physico-mechanical properties of wool fabric was studied in detail. Nano-kaolinite incorporated fire retardant formulations showed high fire retardant performance in terms of inclined flammability test, limiting oxygen index (LOI) and thermogravimetric analysis. The characterization of nanoparticles was performed using various analytical instruments. The results inferred that nano-kaolinite treatment by both application methods is effective for improving the fire resistance of wool fabric. The treatment resulted up to 32% enhancement in fire retardant properties.

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