scholarly journals Development of Biodegradable Flame-Retardant Bamboo Charcoal Composites, Part I: Thermal and Elemental Analyses

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2217 ◽  
Author(s):  
Shanshan Wang ◽  
Liang Zhang ◽  
Kate Semple ◽  
Min Zhang ◽  
Wenbiao Zhang ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Residue Analysis ◽  
Fire Retardant ◽  
Protective Layer ◽  
Growth Index ◽  
Raw Material ◽  
Bamboo Charcoal ◽  
Limiting Oxygen Index ◽  
Plastic Composite

In this study, bamboo charcoal (BC) was used as a substitute filler for bamboo powder (BP) in a lignocellulose-plastic composite made from polylactic acid (PLA), with aluminum hypophosphite (AHP) added as a fire retardant. A set of BC/PLA/AHP composites were successfully prepared and tested for flame-retardancy properties. Objectives were to (a) assess compatibility and dispersibility of BC and AHP fillers in PLA matrix, and (b) improve flame-retardant properties of PLA composite. BC reduced flexural properties while co-addition of AHP enhanced bonding between PLA and BC, improving strength and ductility properties. Adding AHP drastically reduced the heat release rate and total heat release of the composites by 72.2% compared with pure PLA. The formation of carbonized surface layers in the BC/PLA/AHP composites effectively improved the fire performance index (FPI) and reduced the fire growth index (FGI). Flame-retardant performance was significantly improved with limiting oxygen index (LOI) of BC/PLA/AHP composite increased to 31 vol%, providing a V-0 rating in UL-94 vertical flame test. Adding AHP promoted earlier initial thermal degradation of the surface of BC/PLA/AHP composites with a carbon residue rate up to 40.3%, providing a protective layer of char. Further raw material and char residue analysis are presented in Part II of this series.

scholarly journals Enhancement of Flame Retardancy and Mechanical Properties of Polylactic Acid with a Biodegradable Fire-Retardant Filler System Based on Bamboo Charcoal

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2167
Author(s):  
Wenzhu Li ◽  
Liang Zhang ◽  
Weisheng Chai ◽  
Ningning Yin ◽  
Kate Semple ◽  
...  
Keyword(s):  
Heat Release ◽  
Polylactic Acid ◽  
Flame Retardancy ◽  
Chemical Elements ◽  
Fire Retardant ◽  
Strength Properties ◽  
Bamboo Charcoal ◽  
Adhesion Promoter ◽  
Limiting Oxygen Index ◽  
Air Atmosphere

A cooperative flame-retardant system based on natural intumescent-grafted bamboo charcoal (BC) and chitosan (CS) was developed for polylactic acid (PLA) with improved flame retardancy and minimal decline in strength properties. Chitosan (CS) as an adhesion promoter improved the interfacial compatibility between graft-modified bamboo charcoal (BC-m) and PLA leading to enhanced tensile properties by 11.11% and 8.42%, respectively for tensile strength and modulus. At 3 wt.% CS and 30 wt.% BC-m, the crystallinity of the composite increased to 38.92%, or 43 times that of pure PLA (0.9%). CS promotes the reorganization of the internal crystal structure. Thermogravimetric analysis showed significantly improved material retention of PLA composites in nitrogen and air atmosphere. Residue rate for 5 wt.% CS and 30 wt.% BC-m was 29.42% which is 55.1% higher than the theoretical value of 18.97%. Flammability tests (limiting oxygen index-LOI and UL-94) indicated significantly improved flame retardancy and evidence of cooperation between CS and BC-m, with calculated cooperative effectiveness index(Ce) >1. From CONE tests, the peak heat release rate (pHRR) and total heat release (THR) were reduced by 26.9% and 30.5%, respectively, for 3% CS + 20% BC-m in PLA compared with adding 20% BC-m alone. Analysis of carbon residue morphology, chemical elements and structure suggest CS and BC-m form a more stable char containing pyrophosphate. This char provides heat insulation to inhibit complete polymer pyrolysis, resulting in improved flame retardancy of PLA composites. Optimal mix may be recommended at 20% BC-m + 3% CS to balance compatibility, composite strength properties and flame retardance.

scholarly journals Halogen-Free Flame Retardant Polypropylene Fibers with Modified Intumescent Flame Retardant: Preparation, Characterization, Properties and Mode of Action

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2553
Author(s):  
Qibin Xu ◽  
Lei Wu ◽  
Xiang Yan ◽  
Shengchang Zhang ◽  
Linan Dong ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Release ◽  
Flame Retardant ◽  
Protective Layer ◽  
Intumescent Flame Retardant ◽  
X Ray Diffraction ◽  
Limiting Oxygen Index ◽  
Action Mode ◽  
Combustible Gases ◽  
Halogen Free

A novel intumescent flame retardant (IFR) agent designated as Dohor-6000A has been used to prepare halogen-free flame retardant polypropylene (PP) fibers via melting spinning. Before being blended with PP resin, a surface modification of Dohor-6000A was carried out to improve its compatibility with the PP matrix. The rheological behavior of flame retardant Dohor-6000A/PP resin, the structure, morphology, mechanical properties, flammability of the Dohor-6000A/PP fibers were studied in detail, as well as the action mode of flame retardant. X-ray diffraction (XRD) showed that the addition of Dohor-6000A did not damage the crystal as well as the orientation structure of PP matrix, which was helpful to the maintenance of mechanical properties. The presence of the IFR significantly improved the flame retardant performance and thermal stability of PP fibers. When the content of Dohor-6000A reached 25%, the fibers displayed a limiting oxygen index (LOI) value of 29.1% and good melt-drop resistance. Moreover, the peak heat release rate (PHRR) and total heat release (THR) from microscale combustion colorimetry (MCC) tests were decreased by 26.0% and 16.0% in comparison with the same conditions for pure PP fibers. In the condensed phase, the IFR promoted a carbonization process and promoted the formation of a glassy or stable foam protective layer on the surface of the polymer matrix. In addition, the IFR decomposed endothermically to release of non-combustible gases such as NH3 and CO2 which dilutes the combustible gases in the combustion zone.

scholarly journals Role of Copper Oxide on Epoxy Coatings with New Intumescent Polymer-Based Fire Retardant

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5978
Author(s):  
Riyazuddin ◽  
Samrin Bano ◽  
Fohad Mabood Husain ◽  
Jamal Akhter Siddique ◽  
Khadijah H. Alharbi ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Heat Release ◽  
Flame Retardant ◽  
Cone Calorimeter ◽  
Elevated Temperatures ◽  
Fire Retardant ◽  
Intumescent Flame Retardant ◽  
Gravimetric Analysis ◽  
Sem Images ◽  
Major Drawback

Epoxy resins (EP) have been used as a thermos-setting material in the field of coating, casting, bonding agent, and laminating. However, a major drawback associated with its use is the lack of good flaming properties, and it is responsible for heavy smoke along with hazardous gases considerably limiting its uses in various fields. In this study, N-ethanolamine triazine-piperizine, a melamine polymer (ETPMP), was established as a new charring-foaming agent and was successfully synthesized with ethanolamine, piperizine, cyanuric chloride, and melamine as precursor molecules via the nucleophilic substitution reaction method. Elemental analysis and Fourier transform infrared (FTIR) spectroscopy analysis were applied to approve the synthesis of ETPMP and confirmation of its structure and characterization. The epoxy coating of intumescent flame retardant (IFR) was equipped by introducing ETPMP, ammonium polyphosphate (APP), and copper oxide (CuO) in multiple composition ratios. CuO was loaded at various amounts into the IFR-coating system as a synergistic agent. The synergistic action of CuO on IFR coatings was scientifically examined by using different analytical tests such as vertical burning test (UL-94V), limited oxygen index (LOI), thermal gravimetric analysis (TGA), cone calorimeter, and scanning electron microscope (SEM). The results showed that small changes in the amount of CuO expressively amplified the LOI results and enhanced the V-0 ratings in the UL-94V test. The TGA data clearly demonstrate that the inclusion of CuO can transform the thermal deprivation behavior of coatings with a growing char slag proportion with elevated temperatures. Information from cone calorimeter data affirmed that CuO can decrease the burning factors by total heat release (THR) together with peak heat release rate (PHRR). The SEM images indicated that CuO can enrich the power and compression of the intumescent char that restricts the movement of heat and oxygen. Our results demonstrate a positive influence of CuO on the epoxy-headed intumescent flame retardant coatings.

scholarly journals Synergistic Effects of Black Phosphorus/Boron Nitride Nanosheets on Enhancing the Flame-Retardant Properties of Waterborne Polyurethane and Its Flame-Retardant Mechanism

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1487 ◽  
Author(s):  
Sihao Yin ◽  
Xinlin Ren ◽  
Peichao Lian ◽  
Yuanzhi Zhu ◽  
Yi Mei
Keyword(s):  
Boron Nitride ◽  
Heat Release ◽  
Flame Retardant ◽  
Hexagonal Boron Nitride ◽  
Synergistic Effects ◽  
Waterborne Polyurethane ◽  
Black Phosphorus ◽  
Limiting Oxygen Index ◽  
Polyurethane Composite ◽  
Black Phosphorene

We applied black phosphorene (BP) and hexagonal boron nitride (BN) nanosheets as flame retardants to waterborne polyurethane to fabricate a novel black phosphorus/boron nitride/waterborne polyurethane composite material. The results demonstrated that the limiting oxygen index of the flame-retarded waterborne polyurethane composite increased from 21.7% for pure waterborne polyurethane to 33.8%. The peak heat release rate and total heat release of the waterborne polyurethane composite were significantly reduced by 50.94% and 23.92%, respectively, at a flame-retardant content of only 0.4 wt%. The superior refractory performances of waterborne polyurethane composite are attributed to the synergistic effect of BP and BN in the gas phase and condensed phase. This study shows that black phosphorus-based nanocomposites have great potential to improve the fire resistance of polymers.

scholarly journals Self-Extinguishing Resin Transfer Molding Composites Using Non-Fire-Retardant Epoxy Resin

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2554 ◽  
Author(s):  
Zhi Geng ◽  
Shuaishuai Yang ◽  
Lianwang Zhang ◽  
Zhenzhen Huang ◽  
Qichao Pan ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Flame Retardants ◽  
Resin Transfer Molding ◽  
Fire Retardant ◽  
Functional Materials ◽  
Building Blocks ◽  
Fire Retardancy ◽  
Limiting Oxygen Index ◽  
Transfer Molding ◽  
Halogen Free

Introducing fire-retardant additives or building blocks into resins is a widely adopted method used for improving the fire retardancy of epoxy composites. However, the increase in viscosity and the presence of insoluble additives accompanied by resin modification remain challenges for resin transfer molding (RTM) processing. We developed a robust approach for fabricating self-extinguishing RTM composites using unmodified and flammable resins. To avoid the effects on resin fluidity and processing, we loaded the flame retardant into tackifiers instead of resins. We found that the halogen-free flame retardant, a microencapsulated red phosphorus (MRP) additive, was enriched on fabric surfaces, which endowed the composites with excellent fire retardancy. The composites showed a 79.2% increase in the limiting oxygen index, a 29.2% reduction in heat release during combustion, and could self-extinguish within two seconds after ignition. Almost no effect on the mechanical properties was observed. This approach is simple, inexpensive, and basically applicable to all resins for fabricating RTM composites. This approach adapts insoluble flame retardants to RTM processing. We envision that this approach could be extended to load other functions (radar absorbing, conductivity, etc.) into RTM composites, broadening the application of RTM processing in the field of advanced functional materials.

Flammability and thermal properties of cotton fabrics modified with a novel flame retardant containing triazine and phosphorus components

2016 ◽  
Vol 87 (11) ◽  
pp. 1367-1376 ◽  
Author(s):  
Chaohong Dong ◽  
Zhou Lu ◽  
Peng Wang ◽  
Ping Zhu ◽  
Xuechao Li ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Cotton Fabric ◽  
Flame Retardancy ◽  
Decomposition Temperature ◽  
Cotton Fabrics ◽  
Cone Calorimetry ◽  
Limiting Oxygen Index ◽  
Untreated Cotton ◽  
Index Value

A novel formaldehyde-free flame retardant containing phosphorus and dichlorotriazine components (CTAP) for cotton fabrics was synthesized. As an active group, the dichlorotriazine could react with cotton fabric via covalent reaction. The addition of 20.7 wt% CTAP into the cotton fabric obtained a high limiting oxygen index value of 31.5%, which was 13.5% higher than the pure cotton fabric. The results of heat release rate, total heat release and effective heat combustion indicated that CTAP effectively imparted flame retardancy to cotton fabric by the cone calorimetry test. With respect to the untreated cotton fabrics, the treated cotton fabrics degraded at lower decomposition temperature and form a consistent and compact char layer, which could be observed by thermogravimetric analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. Compared to the untreated cotton fabrics, CTAP performed an effective role in flame retardancy for treated cotton fabrics. Meanwhile, it stimulated the formation of char and promoted the thermal stability of treated cotton fabrics during combustion.

scholarly journals Flame-Retardant and Thermal Degradation Mechanism of Caged Phosphate Charring Agent with Melamine Pyrophosphate for Polypropylene

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Xuejun Lai ◽  
Jiedong Qiu ◽  
Hongqiang Li ◽  
Xingrong Zeng ◽  
Shuang Tang ◽  
...  
Keyword(s):  
Thermal Degradation ◽  
Heat Release ◽  
Flame Retardant ◽  
Heat Release Rate ◽  
Release Rate ◽  
Degradation Mechanism ◽  
Limiting Oxygen Index ◽  
Thermal Degradation Mechanism ◽  
Charring Agent ◽  
Ul 94

An efficient caged phosphate charring agent named PEPA was synthesized and combined with melamine pyrophosphate (MPP) to flame-retard polypropylene (PP). The effects of MPP/PEPA on the flame retardancy and thermal degradation of PP were investigated by limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetric test (CCT), and thermogravimetric analysis (TGA). It was found that PEPA showed an outstanding synergistic effect with MPP in flame retardant PP. When the content of PEPA was 13.3 wt% and MPP was 6.7 wt%, the LOI value of the flame retardant PP was 33.0% and the UL-94 test was classed as a V-0 rating. Meanwhile, the peak heat release rate (PHRR), average heat release rate (AV-HRR), and average mass loss rate (AV-MLR) of the mixture were significantly reduced. The flame-retardant and thermal degradation mechanism of MPP/PEPA was investigated by TGA, Fourier transform infrared spectroscopy (FTIR), TG-FTIR, and scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDXS). It revealed that MPP/PEPA could generate the triazine oligomer and phosphorus-containing compound radicals which changed the thermal degradation behavior of PP. Meanwhile, a compact and thermostable intumescent char was formed and covered on the matrix surface to prevent PP from degrading and burning.

scholarly journals Novel P/Si Based Nanoparticles for Durable Flame Retardant Application on Cotton

2021 ◽  
Author(s):  
Na Li ◽  
Panpan Chen ◽  
Dongni Liu ◽  
Gaowei Kang ◽  
Liu Liu ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Dip Coating ◽  
Gas Chromatography Mass Spectrometry ◽  
Cotton Fibers ◽  
Pyrolysis Gas ◽  
Limiting Oxygen Index ◽  
Potential Safety ◽  
Ft Ir

Abstract Cotton fibers as original materials of cotton fabrics have a widely application due to its perfect hygroscopicity, air permeability and largest annual output. However, cotton materials have potential safety hazard during its application because of flammability (limiting oxygen index is about 18%). In order to improve the flame retardancy of cotton fibers and reduce the damage of its mechanical properties, novel P/Si based flame retardant (PFR) nanoparticles were synthesized by one-step radical polymerization. Vinyl phosphoric acid and tetramethyl divinyl disiloxane were introduced into the nanoparticles. The structure, morphology and thermal stability of PFR was characterized by fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis test (TGA). Durable flame retardant cotton fibers were prepared by dip-coating and plasma induced crosslinking methods. Micro-calorimeter (MCC) characterization showed that the peak of heat release rate (pHRR) and the total heat release were reduced by 47.3% and 29.8% for modified cotton fibers compared with pure cotton fibers. Limiting oxygen index (LOI) of modified cotton fibers was increased to 27%. The residue carbon of modified cotton fibers was 19.0% at 700 o C, while the value of pure cotton fibers was 3.0%. Besides, durability of the modified cotton fibers was approved by cyclic washing test. In addition, flame retardant mechanism was revealed by collecting and analyzing condensed and gaseous pyrolysis products. The data of FE-SEM for residue carbon, FT-IR spectra of products at different pyrolysis temperatures and pyrolysis gas chromatography mass spectrometry (Py-GC-MS) showed that PFR was a synergistic flame retardant contained barrier and quenching effecting applied on cotton materials.

scholarly journals Preparation of Mn2+ Doped Piperazine Phosphate as a Char-Forming Agent for Improving the Fire Safety of Polypropylene/Ammonium Polyphosphate Composites

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7589
Author(s):  
Fuqiang Dong ◽  
Zhonglin Luo ◽  
Biaobing Wang
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Fire Safety ◽  
Raw Materials ◽  
Carbon Layer ◽  
Ammonium Polyphosphate ◽  
Manganese Acetate ◽  
Limiting Oxygen Index ◽  
Peak Heat Release Rate ◽  
High Degree

A piperazine phosphate doped with Mn2+ (HP-Mn), as a new char-forming agent for intumescent flame retardant systems (IFR), was designed and synthesized using 1-hydroxy ethylidene-1,1-diphosphonic acid, piperazine, and manganese acetate tetrahydrate as raw materials. The effect of HP-Mn and ammonium polyphosphate (APP) on the fire safety and thermal stability of polypropylene (PP) was investigated. The results showed that the combined incorporation of 25 wt.% APP/HP-Mn at a ratio of 1:1 endowed the flame retardant PP (PP6) composite with the limiting oxygen index (LOI) of 30.7% and UL-94 V-0 rating. In comparison with the pure PP, the peak heat release rate (PHRR), the total heat release (THR), and the smoke production rate (PSPR) of the PP6 were reduced by 74%, 30%, and 70%, respectively. SEM and Raman analysis of the char residues demonstrated that the Mn2+ displayed a catalytic cross-linking charring ability to form a continuous and compact carbon layer with a high degree of graphitization, which can effectively improve the flame retardancy of PP/APP composites. A possible flame-retardant mechanism was proposed to reveal the synergistic effect between APP and HP-Mn.

scholarly journals Environmentally Benign Phytic Acid-Based Nanocoating for Multifunctional Flame-Retardant/Antibacterial Cotton

Fibers ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 69
Author(s):  
Eva Magovac ◽  
Bojana Vončina ◽  
Ana Budimir ◽  
Igor Jordanov ◽  
Jaime C. Grunlan ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Phytic Acid ◽  
Environmentally Benign ◽  
Lower Amount ◽  
Layer By Layer ◽  
Limiting Oxygen Index ◽  
Untreated Cotton ◽  
Microscale Combustion Calorimeter ◽  
Combustion Calorimeter

Environmentally benign layer-by-layer (LbL) deposition was used to obtain flame-retardant and antimicrobial cotton. Cotton was coated with 8, 10, and 12 phytic acid (PA) and chitosan (CH)-urea bilayers (BL) and then immersed into copper (II) sulfate (CuSO4) solution. Our findings were that 12 BL of PA/CH-urea + Cu2+ were able to stop flame on cotton during vertical flammability testing (VFT) with a limiting oxygen index (LOI) value of 26%. Microscale combustion calorimeter (MCC) data showed a reduction of peak heat release rates (pHRR) of more than 61%, while the reduction of total heat release (THR) was more than 54%, relative to untreated cotton. TG-IR analysis of 12 BL-treated cotton showed the release of water, methane, carbon dioxide, carbon monoxide, and aldehydes, while by adding Cu2+ ions, the treated cotton produces a lower amount of methane. Treated cotton also showed no levoglucosan. The intumescent behavior of the treatment was indicated by the bubbled structure of the post-burn char. Antibacterial testing showed a 100% reduction of Klebsiella pneumoniae and Staphylococcus aureus. In this study, cotton was successfully functionalized with a multifunctional ecologically benign flame-retardant and antibacterial nanocoating, by means of LbL deposition.

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