scholarly journals Improving Fire Retardancy of Beech Wood by Graphene

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 303 ◽  
Author(s):  
Ayoub Esmailpour ◽  
Roya Majidi ◽  
Hamid R. Taghiyari ◽  
Mehdi Ganjkhani ◽  
Seyed Majid Mohseni Armaki ◽  
...  

The aim of this paper was to improve the fire retardancy of beech wood by graphene. Six fire properties, namely time to onset of ignition, time to onset of glowing, back-darkening time, back-holing time, burnt area and weight loss were measured using a newly developed apparatus with piloted ignition. A set of specimens was treated with nano-wollastonite (NW) for comparison with the results of graphene-treated specimens. Graphene and NW were mixed in a water-based paint and brushed on the front and back surface of specimens. Results demonstrated significant improving effects of graphene on times to onset of ignition and glowing. Moreover, graphene drastically decreased the burnt area. Comparison between graphene- and NW-treated specimens demonstrated the superiority of graphene in all six fire properties measured here. Fire retardancy impact of graphene was attributed to its very low reaction ability with oxygen, as well as its high and low thermal conductivity in in-plane and cross-section directions, respectively. The improved fire-retardancy properties by the addition of graphene in paint implied its effectiveness in hindering the spread of fire in buildings and structures, providing a longer timespan to extinguish a fire, and ultimately reducing the loss of life and property. Based on the improvements in fire properties achieved in graphene-treated specimens, it was concluded that graphene has a great potential to be used as a fire retardant in solid wood species.

2011 ◽  
Vol 477 ◽  
pp. 175-184
Author(s):  
Qing Qing Ye ◽  
Xiao Qian Qian ◽  
Jun Ying Lai

The environmental fire retardant mentioned in this paper was compounded of disodium octaborate tetrahydrate and silicon dioxygen(SiO2)gels. Specimens of Chinese fir were impregnated with the compound by pressure and its fire retardant performance was studied. Results showed that, the anti-loss performance of disodium octaborate tetrahydrate was improved obviously. Compared with the untreated specimen, total heat release of the treated specimens decreased by 44.5% on average, while heat release rate decreased by 50.85% on average and ignition time prolonged obviously, which indicates that this compound possess good fire retardancy effect


2018 ◽  
Vol 64 (3) ◽  
pp. 105-114 ◽  
Author(s):  
Masayuki Kawarasaki ◽  
Ryoichi Hiradate ◽  
Yasushi Hirabayashi ◽  
Shinichi Kikuchi ◽  
Yoshifumi Ohmiya ◽  
...  

2018 ◽  
Vol 25 (06) ◽  
pp. 1850113
Author(s):  
HA-SUNG KONG ◽  
BYOUNG-JU KIM ◽  
KWANG-SUN KANG

Bright luminescence was achieved with excess amount of aluminum hydroxide with silica spheres. Various amounts of aluminum hydroxide were attached to silica spheres to improve the performance of fire retardancy. Although silica spheres attached with 60[Formula: see text]wt.% of AlCl3 (AlOH-A) showed no color change and luminescent chromophores, silica spheres attached with 80[Formula: see text]wt.% of (AlOH-B) and 100% of (AlOH-C) of AlCl3 changed the color and produced luminescent chromophores. The solution colors became intense yellow and brown for AlOH-B and AlOH-C, respectively, after 15 days. The FTIR spectra showed the characteristic absorption peaks of Al–OH and Si–O–Al. The concentration dependent photoluminescence (PL) intensities were continuously increased until 242[Formula: see text]mg addition of the colored solution and then slightly decreased thereafter for both AlOH-B and AlOH-C. The PL peaks shifted toward red by increasing the excitation wavelength for both AlOH-B and AlOH-C. Large Stoke shifts, such as 73 and 68[Formula: see text]nm for AlOH-B and AlOH-C, respectively, were observed.


Holzforschung ◽  
2020 ◽  
Vol 74 (4) ◽  
pp. 372-381
Author(s):  
Saara Hautamäki ◽  
Michael Altgen ◽  
Daniela Altgen ◽  
Erik Larnøy ◽  
Tuomas Hänninen ◽  
...  

AbstractIn built environments the combustibility of wood is a great concern, which limits the use of wood as a building material due to legislation. The reaction-to-fire properties of wood can be altered with the use of fire-retardant chemicals, and most of the commonly used fire retardants already have a long history of use. However, only limited information is available on the impact of different fire retardants on the adhesion properties of wood. Additionally, comparative studies between chemicals from different groups of fire retardants is scarce. The objective of this study was to investigate and compare the effects of two commonly used fire retardants, sodium silicate (SS) and diammonium phosphate (DAP), on veneer properties, the focus being especially on thermal behavior and adhesion. Thermal properties and combustibility were studied using thermogravimetric analysis (TGA), flame test and calorimetry. Glue bond strength was analyzed with an automated bonding evaluation system (ABES) and the leaching of chemicals was determined according to EN84. Additionally, the surface characteristics of modified veneers were imaged with scanning electron microscopy (SEM). Results revealed notable differences in the thermal properties of SS and DAP, with DAP having better fire-retardant performance in all thermal testing. SS also affected thermal properties and combustibility of modified veneers, but the effect was only moderate compared to DAP. Neither SS or DAP had any significant resistance against leaching but ABES testing showed a notable increase in the glue bond strength of DAP modified veneers.


Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 955 ◽  
Author(s):  
Demiao Chu ◽  
Jun Mu ◽  
Stavros Avramidis ◽  
Sohrab Rahimi ◽  
Shengquan Liu ◽  
...  

To enhance compression stability and fire retardancy of densified wood, a new modification method i.e., combined nitrogen–phosphorus (NP) fire retardant pre-impregnation with surface thermo-mechanical densification is used to fabricate a certain thickness of functionalized surface layer on poplar. This combined treated wood is investigated via vertical density profile (VDP), and the compression stability is revealed by both soaking test and cone analysis. Results demonstrate that the combined treatment hardened the surface of wood and reformed the interface combination of the NP with the wood cell wall, thus making the surface tissue more close-grained. Fire retardancy was also enhanced; the total heat release and CO generation values decreased by 21.9% and 68.4%, respectively, when compared with that of solely NP-treated wood. Moreover, surface hardness increased by 15.8%, and the recovery of surface hardness and thickness were 56.8% and 77.2% lower than that of simply densified wood. It appears that this NP-involved thermal densification could be considered as an alternative approach to enhance both the compression stability and fire resistance of wood.


2019 ◽  
Vol 34 (1) ◽  
pp. 96-106 ◽  
Author(s):  
Chao Zheng ◽  
Dongfang Li ◽  
Monica Ek

Abstract Sustainable thermal insulating materials produced from cellulosic fibers provide a viable alternative to plastic insulation foams. Industrially available, abundant, and inexpensive mechanical pulp fiber and recycled textile fiber provide potential raw materials to produce thermal insulating materials. To improve the fire retardancy of low-density thermal insulating materials produced from recycled cotton denim and mechanical pulp fibers, bio-based fire retardants, such as sulfonated kraft lignin, kraft lignin, and nanoclays, were coated onto sustainable insulating material surfaces to enhance their fire retardancy. Microfibrillated cellulose was used as a bio-based binder in the coating formula to disperse and bond the fire-retardant particles to the underlying thermal insulating materials. The flammability of the coated thermal insulating materials was tested using a single-flame source test and cone calorimetry. The results showed that sulfonated kraft lignin-coated cellulosic thermal insulating materials had a better fire retardancy compared with that for kraft lignin with a coating weight of 0.8 kg/m2. Nanoclay-coated samples had the best fire retardancy and did not ignite under a heat flux of 25 kW/m2, as shown by cone calorimetry and single-flame source tests, respectively. These cost-efficient and bio-based fire retardants have broad applications for improving fire retardancy of sustainable thermal insulating materials.


Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2554 ◽  
Author(s):  
Zhi Geng ◽  
Shuaishuai Yang ◽  
Lianwang Zhang ◽  
Zhenzhen Huang ◽  
Qichao Pan ◽  
...  

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.


2014 ◽  
Vol 33 (22) ◽  
pp. 2021-2033 ◽  
Author(s):  
Ahmad Bilal ◽  
Richard JT Lin ◽  
Krishnan Jayaraman

A parametric study on the flammability characteristics of rice husk-reinforced polyethylene composites with various material compositions was conducted to find the “best” composites’ formulation for fire retardancy. Composites were manufactured using rice husk, maleated anhydride polyethylene and linear medium density polyethylene. The blends for manufacturing of composites were selected using mixture design approach. The individual effects of each constituent material on the fire performance of composites by cone calorimeter were studied using trace and contour plots for the various thermal and flammability properties. Regression coefficients were also estimated for each measured response. The cone calorimetry results show that the addition of rice husk improved fire retardancy of composites. The addition of maleated anhydride polyethylene did not influence the flammability properties much, except for mass loss rate and specific extinction area. The optimum mixture of rice husk, maleated anhydride polyethylene and linear medium density polyethylene for overall “best” flammability properties of the composites was also determined by multiple response optimisation using the regression models in Design Expert software. The optimum mixture for overall “best” fire retardant properties was found to be 50 wt% of rice husk, 5.6 wt% of maleated anhydride polyethylene and 44.4 wt% of linear medium density polyethylene. The flammability properties measured from composites manufactured with this formulation closely matched the values predicted by the model.


2015 ◽  
Vol 66 ◽  
pp. 157-160 ◽  
Author(s):  
Xudong Cheng ◽  
Yong Zhou ◽  
Kaiyuan Li ◽  
Hui Yang ◽  
Heping Zhang

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