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.

Flame-retardant activity of modified boron nitride nanosheets to cotton

2019 ◽  
Vol 90 (5-6) ◽  
pp. 512-522 ◽  
Author(s):  
Hong Liu ◽  
Yang Du ◽  
Shaohua Lei ◽  
Zhuoqun Liu
Keyword(s):  
Boron Nitride ◽  
Flame Retardant ◽  
Hexagonal Boron Nitride ◽  
Cotton Fabrics ◽  
High Yield ◽  
Limiting Oxygen Index ◽  
Boron Nitride Nanosheets ◽  
Boron Nitride Powder ◽  
Coated Fabrics ◽  
Index Value

Boron nitride nanosheets (BNN) were prepared by molten hydroxide-assisted liquid exfoliation from hexagonal boron nitride powder with an effectively high yield, and then modified with hexachlorocyclotriphosphazene (HCCP) to obtain HCCP-BNN. The series of samples were applied to prepare flame-retardant cotton fabrics with the impregnation-drying method, and successful treatment was confirmed by scanning electron microscopy. The combustion performance of the as-prepared cotton fabrics was tested and evaluated. After coating with HCCP-BNN, the combustion rate of the fabric is reduced in vertical and horizontal combustion conditions and the limiting oxygen-index value of cotton fabric increases to 24.1, becoming less flammable than the blank cotton. The fibrous structure of the BNN and HCCP-BNN coated fabrics is relatively complete after combustion, which indicates that BNN have a certain protective effect on the fabric. The results demonstrate HCCP-BNN as an effective flame-retardant for cotton fabrics.

Synergistic effects of red phosphorus masterbatch with expandable graphite on the flammability and thermal stability of polypropylene/thermoplastic polyurethane blends

2019 ◽  
Vol 28 (3) ◽  
pp. 209-219 ◽  
Author(s):  
Na Wang ◽  
Lingtong Li ◽  
Yang Xu ◽  
Kun Zhang ◽  
Xiaolang Chen ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Heat Release ◽  
Flame Retardant ◽  
Synergistic Effects ◽  
Thermoplastic Polyurethane ◽  
Expandable Graphite ◽  
Gravimetric Analysis ◽  
Red Phosphorus ◽  
Limiting Oxygen Index ◽  
Ul 94

The flammability characterization and synergistic effects of red phosphorus masterbatch (RPM) with expandable graphite (EG) in flame-retardant polypropylene (PP)/thermoplastic polyurethane (TPU) composites are investigated by limiting oxygen index, UL-94 testing, cone calorimeter tests, thermal gravimetric analysis, Fourier transform infrared (FTIR), and scanning electron microscopy. The results show that the flame retardancy of PP/TPU/EG/RPM composites is greatly influenced by RPM. The synergistic effects between RPM and EG take place in the flame-retardant composites. The presence of RPM with EG decreases significantly the heat release rates and total heat release, and UL-94 V-0 rating is achieved when suitable amount of RPM substitutes for EG in the PP/TPU/EG/RPM composites. The T onset and T 10 wt% of the composites are improved because of the presence of RPM. The FTIR spectra show that the incorporation of RPM improves the thermo-oxidative stability of PP/TPU at higher temperatures. The morphological observations indicate the reinforcement of thermal stability, and flame-retardant performance is attributed to the compact and stable char layers promoted by RPM with EG acted as an effective heat barrier and thermal insulation.

Modified expandable graphite as an effective flame retardant for LLDPE/EVA composites filled with Mg(OH)2/Al(OH)3

2019 ◽  
Vol 33 (7) ◽  
pp. 938-955
Author(s):  
Nian Liu ◽  
Na Wang ◽  
Lingtong Li ◽  
Weidi He ◽  
Jianbing Guo ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Synergistic Effects ◽  
Ethylene Vinyl Acetate ◽  
Gas Production ◽  
Expandable Graphite ◽  
Limiting Oxygen Index ◽  
Cone Calorimeter Test ◽  
Ul 94

The flammability, thermal properties, and synergistic effects of modified expandable graphite (MEG) with magnesium hydroxide (MH) and aluminum hydroxide (ATH) on the linear low-density polyethylene/ethylene vinyl acetate (LLDPE/EVA) blends are investigated by Underwriters Laboratories-94 (UL-94) vertical combustion test, limiting oxygen index (LOI), thermogravimetric analysis (TGA), cone calorimeter test (CCT), and scanning electron microscopy (SEM). The results show that the MEG improves the flame-retardant efficiency of LLDPE/EVA blends. The addition of MEG apparently improves the LOI values and the UL-94 rating of LLDPE/EVA composites. The data obtained from the CCT show that the heat release rate (HRR), the total heat release (THR), and the gas production rate of composites with MEG decrease remarkably with increasing the content of MEG. When 10 phr of MEG is added, the char residues of LEMEG10 increase to 38.2% from 2.7% of LLDPE/EVA. The results of SEM and CCT present that MEG can improve the quality of char layers. The rate of char formation is enhanced also due to the existence of MEG, which plays an important role to improve the flame retardancy of the LLDPE/EVA composites.

Monolayer Hexagonal Boron Nitride Tunnel Barrier Contact for Low-Power Black Phosphorus Heterojunction Tunnel Field-Effect Transistors

Nano Letters ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 3963-3969 ◽  
Author(s):  
Seungho Kim ◽  
Gyuho Myeong ◽  
Jihoon Park ◽  
Kenji Watanabe ◽  
Takashi Taniguchi ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Low Power ◽  
Field Effect ◽  
Field Effect Transistors ◽  
Hexagonal Boron Nitride ◽  
Black Phosphorus ◽  
Tunnel Barrier

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.

Synergistic Effects of Nanoporous Nickel Phosphates VSB-1 on Intumescent Flame Retardant Polypropylene Composites

2014 ◽  
Vol 881-883 ◽  
pp. 863-866
Author(s):  
Chao Peng ◽  
Shi Bin Nie ◽  
Lei Liu ◽  
Qi Lin He ◽  
Yuan Hu ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Flame Retardants ◽  
Synergistic Effects ◽  
Intumescent Flame Retardant ◽  
Total Heat Release ◽  
Cone Calorimetry ◽  
Polypropylene Composites ◽  
Intumescent Flame Retardants ◽  
Nickel Phosphates

Nanoporous nickel phosphates (VSB-1) was synthesized by hydrothermal method. Then VSB-1 was added to the ammonium polyphosphate and pentaerythritol system in polypropylene (PP) matrix.The synergistic effect of VSB-1 with intumescent flame retardants (IFR) was studied by cone calorimetry test. The results of cone calorimetry show that heat release rate peak (pHRR) and total heat release (THR) of intumescent flame retardant PP with 2wt% VSB-1 decrease remarkably compared with that of without VSB-1. The pHRR and THR decrease respectively from 1140 to 286.0 kW/m2, and from 96.0 to 63.2 MJ/m2.

Enhanced thermal conductivity and flame retardancy of polyamide 6/flame retardant composites with hexagonal boron nitride

2018 ◽  
Vol 38 (8) ◽  
pp. 767-774 ◽  
Author(s):  
Liang Wang ◽  
Luchong Zhang ◽  
Andreas Fischer ◽  
Yuhua Zhong ◽  
Dietmar Drummer ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Boron Nitride ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
High Performance ◽  
Heat Dissipation ◽  
Hexagonal Boron Nitride ◽  
Light Emitting Diode ◽  
Polyamide 6 ◽  
Twin Screw

Abstract High performance composite of polyamide 6 (PA6)/flame retardant (FR)/hexagonal boron nitride (hBN) was prepared via twin screw extrusion, followed by injection molding. The heat dissipation of the composite was significantly improved by incorporating 40 vol% of hBN, and the corresponding thermal conductivity was up to 5.701 W/(m·K), nearly 17 times that of the PA6/FR composites. In addition, the combination effect of hBN and FR to the flame retardancy of the composites was observed, and the addition of hBN could dramatically enhance the flame retardancy of composites, achieving a UL94 V-0 rating with a limited oxygen index (LOI) value of 37%. This multifunctional modification would broaden the application field of PA6 composites in light-emitting diode (LED) lamps, electronic products, and so on.

Transport properties of ultrathin black phosphorus on hexagonal boron nitride

2015 ◽  
Vol 106 (8) ◽  
pp. 083505 ◽  
Author(s):  
Rostislav A. Doganov ◽  
Steven P. Koenig ◽  
Yuting Yeo ◽  
Kenji Watanabe ◽  
Takashi Taniguchi ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Transport Properties ◽  
Hexagonal Boron Nitride ◽  
Black Phosphorus

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.

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