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1.
Daisuke Kamikawa Katsushi Kuroda Mariko Inoue Satoshi Kubo Takahiro Yoshida 《Journal of Wood Science》2009,55(6):453-457
In this study, the combustion properties of wood pellets were evaluated using a cone calorimeter, which is usually used to
verify the fireproof performance of architectural materials. In contrast to the conventional methods including combustion
calorimetry and thermogravimetric analysis, a cone calorimeter can estimate various combustion parameters, e.g., changes of
heat release rate (HRR), weight decrease during burning process, ignition time, and flame-out and burn-out time as well as
combustion heat, in a single experimental run with no pretreatment for sample size reduction. The following results were obtained
by the combustion test of Japanese cedar (Cryptomeria japonica) and larch (Larix kaempferi) wood pellets having various volume densities. Ignition time of wood pellet became slower with increasing volume density
of the pellets. However, burn-out time was not clearly correlated to volume density. The heat release values measured by cone
calorimeter could be comparable to those from the conventional combustion calorimeters, and flaming heat values of the bark
pellets were always lower in comparison with pellets made of xylem, although total heat release was almost the same. 相似文献
2.
杨木纤维/无机纳米Al2O3复合材料的阻燃性能 总被引：1，自引：0，他引：1
采用锥形量热仪法研究了杨木纤维／无机纳米Al2O3复合材料的点燃时间、热释放速率、总热释放量、有效燃烧热、质量损失速率等。实验结果表明,通过无机纳米Al2O3改性后,点燃时间延长了1倍;45s和175s出现的热释放峰值明显减弱,热释放速率明显降低,平均热释放速率下降了38％,热释放速率峰值下降了25％;总释放热下降了38％;175s的放热峰出现前,其有效燃烧值略低于空白纤维板材,并且两者都比较平缓;质量损失与燃烧时热释放速率同步。 相似文献
3.
GAO Li WANG Zheng CHANG Liang Research Institute of Wood Industry China Academy of Forestry Beijing P. R. China 《中国林业科技(英文版)》2008,(2)
Flammability properties of composites of wood fiber and recycled plastic were evaluated by the cone calorimeter and oxygen index chamber. Results were shown as follows: 1) Wood-PVC composite showed worse thermal stability on time to ignition (TTI) and mean heat release rate (MHRR), but better performance on heat release rate (HRR) and mean efficient heat of combustion (MEHC); wood-PP composite had better thermal stability properties, but was worse on other fire performance; 2) Compared with wood-PVC composi... 相似文献
4.
采用锥形量热仪(CONE)研究可膨胀石墨(EG)与聚磷酸铵(APP)对木粉/聚丙烯复合材料的协同阻燃作用。CONE测试结果表明:EG和APP均可降低木粉/聚丙烯复合体系的热释放速率(HRR)、总热释放(THR)和烟释放速率(RSR),提高成炭率;与APP相比,EG表现出更好的抑烟效果。当EG与APP的总添加量为15%、复配比例为2∶1时,能形成稳定致密的膨胀炭层,阻燃协同效应显著。力学性能测试结果表明:即使在马来酸酐接枝聚丙烯相容剂(MAPP)的存在下,EG和APP阻燃剂的添加对复合材料的冲击强度和弯曲强度仍有不利影响,但EG的添加可提高复合材料的弯曲模量。 相似文献
5.
George I. Mantanis Jozef Martinka Charalampos Lykidis Libor Ševčík 《Wood material science & engineering》2020,15(5):303-311
ABSTRACT The objective of the work was to evaluate the efficacy of two new polyphosphate-based fire retardants (FRs) and one commercial product named Siriono® on the fire performance and physical–mechanical properties of medium density fibreboard (MDF) fabricated in the laboratory from Scots pine (Pinus sylvestris L.) wood. The fibres were treated with aqueous solutions of fire retardants, at 12% loading (dry salt on dry wood), and bonded with a melamine urea formaldehyde (MUF) adhesive. The physical and mechanical properties of panels were assessed using the European standards, whereas their fire performance was evaluated using an in-house method and the Cone calorimeter. In overall, the chemicals added enhanced the fire and smoke properties of the panels to varying degrees. Critical FR parameters such as peak heat release rate (peak HRR), total heat release (THR) and total smoke production (TSP) were significantly improved in the FR-treated panels, as exhibited in cone calorimeter tests. However, the internal bond strength of treated panels largely decreased by the addition of fire retardants, while thickness swell and water absorption negatively affected to a significant extent. In contrast, the formaldehyde release of the panels was considerably decreased at the E1 class level, with the incorporation of the polyphosphate-based additives. 相似文献
6.
Fire resistance of thick wood-based boards 总被引：1，自引：0，他引：1
Thick wood-based boards are used as construction materials for walls and floors in Japan. In this study, fire resistance tests
(ISO 834-1) and cone calorimeter tests (ISO 5660-1) were conducted for thick plywood, particleboard, and medium density fiberboard
with sample thicknesses of about 28–30mm, and their suitabilities for quasi-fireproof or fire-preventive structures were evaluated.
In the ISO 834-1 fire resistance test, the heat-shielding performance (insulation criterion) for walls was evaluated and the
results showed that the larger the apparent density of a woodbased board, the higher its insulation performance. The insulation
performance of thick wood-based boards in the fire resistance test could be forecast from the results of the cone calorimeter
test, especially when the second peak of heat release rate appeared. In the cone calorimeter tests, the surface layer density
of the plywood, particleboard, and medium density fiberboard was the dominant parameter for the time to ignition and initial
heat release rate. These results indicate that thick wood-based board is a suitable fire-preventive construction material.
Part of this study was presented at the Annual Meeting of the Architectural Institute of Japan, Hokkaido, Japan, August 2004 相似文献
7.
INTRoDUCTIoNThechemicalscommonlyusedforflameretardantstowoodincludeammoniumphosphate,phosphoricacid,boricacid,borax,hydratedalumna,am-moniasulfate,zincchlorideandmagne--siumcNoridetl'2j.Thesechemicalsareimpregnatedasaqueoussolutionsintothewoodwheretheyaredepositedwithintheporesandcapillariesofthewoodwhenthesolutionevaporates.Butthesechemicalsarenotsuitableforexteriorandunder-groundconstructionwheretheflameretardantsareleachedeasily[3:.Nowanimportantdevelopmentorientationofstudyingonflamere… 相似文献
8.
In this paper, the influence of melamine polyphosphate (MPP) and aluminum hypophosphite (AHP) on mechanical properties, flame retardancy and thermal degradation of high-density polyethylene/wood flour composites (HDPE/WF) was investigated. The synergistic effect of MPP and AHP was investigated. Polyethylene grafted with maleic anhydride (PE-g-MAH) was used as coupling agent. The experimental data demonstrated that the HDPE/WF composites with 35 wt% MPP/AHP (3:2) could achieve a LOI value of 29.6 % and UL-94 V-0 rating. In addition, the cone value also revealed that the heat release rate and the smoke production rate were clearly reduced. SEM results showed that the synergistic system (MPP/AHP = 3:2) could form a dense and thick char layer and good adhesion between wood flour and HDPE matrix, which prevented the transfer of heat flux and fuel gases. Incorporation of MPP and AHP improved the thermal stability of HDPE/wood flour as observed from the thermogravimetric analysis results and also enhanced the thermal resistance of char layer at high temperature based on scanning electron microscopy observation. 相似文献
9.
木材结构特性对氧指数的影响 总被引：2，自引：0，他引：2
采用氧九法对４种树种木材、５种阻燃物质燃烧特性的研究发现，未阻燃木材的氧指数在纵横向上有差异性，纵向高于横向，径弦向差异很小。这主要是木材结构各向异性以及各方向上的导热系数不同所致。木材树种不同氧指数也有差异，原因之一密度不同所致。阻燃处理可使方向上的的差异逆转，即横向高于纵向。同一阻燃物质对不同树种木才的作用效果不同，即树料与阻燃物质之间存在适应性问题。树种铎氧指数有很大影响。 相似文献
10.
Tsunehisa Miki Hiroyuki Sugimoto Keisuke Kojiro Yuzo Furuta Kozo Kanayama 《Journal of Wood Science》2012,58(4):300-308
The thermal properties and transitions of solid and ground wood samples conditioned at different humidity conditions were investigated by temperature-modulated differential scanning calorimetry. A time-dependent transition was detected as an endothermic peak in the total and non-reversing heat flows and as a step change in the reversing heat flow during the first heating run of samples with moisture contents above 5?%, but it disappeared in the second heating run. These different thermal behaviors indicate that the effect of heat and moisture on the thermal properties of wood is history dependent. This step change in the reversing heat flow is considered to be a glass transition of moist wood. Other relaxation processes (e.g., enthalpy relaxation) occur simultaneously with this glass transition. The temperature ranges of the transition and the relaxation decreased drastically as the moisture content increased up to 11?%, while they remained almost constant at higher moisture contents. In addition, the transitions of the ground wood occurred at lower temperatures than those of the solid wood at similar moisture contents. Kissinger plots revealed that the apparent activation energy for the glass transition of the solid wood with a moisture content of 11?% was about 600?kJ/mol, whereas that of the ground wood was 220?kJ/mol. 相似文献
11.
Fireplaysanimportantroleinmakingmancivilization,butfirealsobringaboutdisastertoman.Somedevelopedcountriesdatashowedthatl%ofthegrossnationalproductisdevotedbyconflagrationseveryyear.Inrecentyears,firesoccurredabout3-4hundredtimeseveryyearinChina,di-recteconomiclosswas2Oo-3OOmillionChineseyuanL13,andmostfireswerecausedbywoodburning.Therefore,flameretardanttreatmentforwoodtodiminishorpreventfiredisasterisamosteffectivemeasureofstrategy.Forthisreason,thisresearchfieldhasbeenreceivingagreatat-tC… 相似文献
12.
In order to develop a fireproof wooden material, the synergic effect of fire-retardant chemicals and wood coatings was studied.
The fire performance was evaluated by cone calorimeter. Impregnation of fire retardants including polyphosphatic carbamate,
and ceramic coatings including alkoxy metal salt improved the fire performance of wooden materials. This treatment made it
possible to meet the guidelines for fire performance of noncombustible materials in Japan. In addition to the vacuum-pressure
impregnation treatment, hot-and-cold-bath impregnation treatment is an effective way to develop fire-retardant wood by impregnating
fire retardant and ceramic coating. The weatherability of the developed material was also investigated. The ceramic coating
was resistant to light and moisture.
Part of this report was presented at 54th Annual Meeting (Sapporo, August 2004) and the 55th Annual Meeting (Kyoto, March
2005) of the Japan Wood Research Society 相似文献
13.
Chih-Shen Chuang Te-Hsin Yang Kuang-Chung Tsai Tsung-Yao Tseng Ming-Kuang Wang 《Wood Science and Technology》2013,47(2):353-367
Using intumescent coatings on wood-based materials is an effective method for fire safety. Previous studies have demonstrated that the formulation of components strongly influences the performance of coatings. This study investigated the effect of intumescent formulation of vinyl acetate-acrylic coating on flame retardancy of plywood. The fire retardancy of materials was assessed by both heat release and CO and CO2 emissions. The CO and CO2 emissions have not been used frequently to rank materials; the highly toxic CO and CO2 may cause most fire fatalities. The fire retardancy of coatings on plywood was assessed by a cone calorimeter. Total heat release and time to peak heat release rate were the two primary parameters. The data show that low contents of binder resin (BR) and foam producing substance (FPS) decreased total heat release and lengthened time to peak heat release rate. Additionally, low BR and FPS content can form an ideal char layer. The ideal char layer significantly decreased the CO and CO2 emission. The mechanism to achieve better fire performance was verified by thermogravimetrical analysis exhibiting lower weight loss. Moreover, evaluated by 31P NMR, the low BR and FPS content can extend the survival duration of phosphor-carbonaceous chars. The results provide information for designing vinyl acetate-acrylic emulsion coating. 相似文献
14.
Fengqiang Wang Zhijun Zhang Qingwen Wang Jiayin Tang 《Frontiers of Forestry in China》2008,3(4):487-492
An intumescent waterborne amino-resin fire-retardant coating for wood (C) was synthesized and its fire-retardant and smoke-suppressant
properties were investigated. The main film-builder of C was urea-formaldehyde resin blended with polyvinyl acetate resin.
The intumescent fire-retardant system of C consisted of guanylurea phosphate (GUP), ammonium polyphosphate (APP), pentaerythritol
(PER) and melamine (MEL). Specimens of plywood painted, respectively, with a commercial intumescent fire-retardant coating
(A), a synthesized coating (C), and the main film-builder of coating C (B), as well as an unpainted plywood (S-JHB), were
analyzed by cone calorimetry (CONE). The results show a marked decrease in the heat release rate (HRR) and the total heat
release (THR), an increased mass of residual char (Mass), a marked postponement in time to ignition (TTI) and a reduced carbon
monoxide production rate (P
CO). The smoke production rate (SPR) and total smoke production (TSP) of the plywood painted with coating C were observed with
the CONE test. The overall fire-retardant and smoke-suppressant performance of the synthesized coating C was much better than
that of the commercial coating A. The thermo-gravimetric analysis (TGA) results of coating C and its film-builder B indicated
that the thermal degradation process of B was slowed down by the addition of the intumescent fire-retardant system; the increase
in the amount of charring of coating C was considerable.
__________
Translated from Scientia Silvae Sinicae, 2007, 43(12): 117–121 [译自: 林业科学] 相似文献
15.
Summary The objectives of this research were to investigate the proportion of decayed wood in mature aspen stems, its chemical composition and its potential utility as a fuel or as a substrate for conversion to fine chemicals as part of an integrated utilization scheme. Three sound and ten decayed aspen stems were sampled from a boreal forest site. Stem analysis indicate that on average, 20% of the merchantable stem volume was in advanced decay and that considerable sound wood recovery was possible. Wood specific gravity and chemical composition were determined. The holocellulose content (volumetric basis) in advanced decayed wood was reduced by 67%. Thermal analysis of the wood using a differential scanning calorimeter provided graphical evidence of a different sequence of events occurring during the combustion of decayed wood and a resulting heat content per unit weight that was 40% higher than that of sound aspen wood. A higher degree of enzymatic hydrolysis was attainable with white-rotted aspen wood. Approximately 62% of the theoretical glucose yield was obtained from decayed aspen wood after alkali-peroxide pretreatment followed by a 12 hour hydrolysis using technical grade enzymes. The above information is used to elucidate future opportunities for wood recovery and energy production from decayed wood resources.The authors would like to thank the Ontario Ministry of Natural Resources, Kirkland Lake for their cooperation; and for the technical assistance by Sally Krigstin, John Leigh, Samir Konar, Ganesh Deka and Doug Charles. We would also like to thank Dr. Morris Wayman, University of Toronto, for his advice and inspiration. We are especially grateful to the following persons and companies for supplying us with enzymes and their associated technical literature: Mr. John Bayard of Van Waters & Rogers Ltee, Canada, representing NOVO Industri, Denmark; Mr. Ian Hodge representing the Miles Biotechnology Group, Canada; and Dr. Gunther Eckert, B.A.S.F., Germany for obtaining and forwarding the products and information of Rohm GmbH, Germany. This work has been partially funded by the Edward Johnson Fellowship, University of Toronto 相似文献
16.
NSCFR flame retardant is one of key factors of non-smoke combustible wood-based materials.Thermal analysis,cone calorimetry,Py-GC/MS, scanning electron microscopy(SEM) were utilized to investigate the flame-retardation and smoke-suppression characteristics and mechanisms of NSCFR flame-retardant.The results show that NSCFR flame-retardant could significantly shorten the combustion duration of wood-based materials and completely eliminate the second peak of heat release rate curve,greatly reduce heat release rate, total smoke release,mass loss rate,specific extinction area,and carbon monoxide production and carbon dioxide production,obviously enhance the mass of combustion char residue,effectively retarding the combustion and inhibiting smoke release of the wood-based material;NSCFR flame-retardant exhibits the ability of flame retardancy on wood by the conjunct mechanism of capturing free radical, diluting combustible gas,and catalyzing charring; NSCFR flame-retardant displays smoke suppression effects on wood by absorption action of nano alveolate structure together with the active catalyzing action of ironic molybdate. 相似文献
17.
研究了硫酸催化条件下,将恩茅松在苯酚中液化用于制备酚醛树脂的技术工艺,分析了各工艺参数对思茅松液化效率的影响,测定了由液化产物制备的液化木基酚醛树脂的物理化学性质和胶合强度。结论如下：1）．液比、反应温度、时间和木粉目数是影响液化反应效率的重要因素,液化产物的残渣率均随上述工艺参数值的升高而降低。2）．残渣含量对树脂物化性质和胶合强度均有影响,残渣含量降低,树脂粘度减小,聚合时间缩短,游离酚含量降低,胶合强度升高。3）．甲醛／苯酚摩尔比对树脂的物化性质和胶合强度也有影响,甲醛／苯酚摩尔比增加,树脂粘度增加,聚合时间减少,游离酚含量减低,胶合强度升高。 相似文献
18.
Subyakto Bambang Subiyanto Toshimitsu Hata Shuichi Kawai 《Journal of Wood Science》2003,49(3):241-247
Some tropical fast-growing woods were converted to edge-jointed lumber, and their fire-retardant properties due to chemical
coating were evaluated using cone calorimetry and a standard fire test. The woods used were Indonesian and Malaysian albizia
and gmelina plantation trees, with Japanese hinoki as a reference. The lumber was coated with 100 g/m2 of trimethylol melamine phosphoric acid in a 25% aqueous solution. The treated and untreated lumber was tested in a laboratory-scale
exposure furnace in accordance with JIS A 1304 and the cone calorimeter test with heat flux of 40 kW/m2 following the ISO 5660. Results showed that fire endurance of all lumber was enhanced by the treatment. The fire-retardant
properties were improved with increasing surface density. Though a similar trend was seen, the fire-retardant properties of
the lumber revealed by the cone calorimeter test were inferior to those seen with standard fire test. Addition of thermocouples
to the cone calorimeter allowed us to obtain information on the critical temperature (260°C) and charring temperature (300°C)
of the lumber.
Received: January 23, 2002 / Accepted: July 15, 2002
Acknowledgment The authors thank Dr. Shigehisa Ishihara, Professor Emeritus of the Wood Research Institute, Kyoto University for his suggestions
about this experiment. 相似文献
19.
《Wood material science & engineering》2013,8(1):64-88
Abstract This state-of-the-art report presents the basic concepts of some of the thermo-hydro (TH) and thermo-hydro-mechanical (THM) wood processes that are in use today, i.e. heat treatment, compression of wood in the longitudinal or transverse direction and wood welding. The reasons for the growing interest in TH and THM techniques are discussed, and the development of the different concepts, from first ideas to current status, is briefly presented. The physical and chemical changes that occur in wood during TH and THM processing according to the latest research are also presented. Finally, developments that are close to or already have an industrial application are presented, and the challenges for further development of the heat treatment, compression and wood welding processes are discussed. The TH processing of wood is based entirely on water and heat, and a THM process incorporates an additional mechanical force. The purpose of wood transformation by a TH or a THM process is to improve the intrinsic wood properties, to acquire a form and functionality desired by engineers without changing its eco-friendly characteristics or hindering its further use in the total material life cycle. Only a few of the recently developed techniques, e.g. heat treatment, wood welding and various densification applications, have been industrialized to some extent. There are many reasons for this relatively low transfer of the research results to a full up-scaled industrial production. Some of them are related to unsolved problems at the laboratory level on small-sized samples and others are related to the scaling-up processes in industry. Furthermore, the ageing of heated wood leads to deterioration with time, in some cases there is an unpleasant odour, the strength of the wood decreases substantially and the wood becomes more brittle. These are new challenges which need to be resolved by the collaboration of researchers from the different scientific domains of academia, research institutes and industry. 相似文献
20.
Vibrational properties of heat-treated green wood 总被引：2，自引：0，他引：2
To investigate the influence of water on heat treatment, green wood was heat-treated. Sitka spruce (Picea sitchensis Carr.) with about 60% moisture content (MC) was used. Young's modulus and loss tangent were measured by the free-free flexural vibration test. The specimens were heated in nitrogen at 160°C for 0.5h. The results were as follows. (1) Recognizing that the effects of heat treatment are mild and that the same specimens cannot be used for both heat treatment and as controls, it was necessary to investigate the effects of the heat treatment based on the variations of properties in the whole of the test lumber. (2) Young's modulus increased and the loss tangent decreased due to heat treatment. When the vibrational properties were measured at various MCs, the MCs at the maximum value of Young's modulus and the minimum value of the loss tangent were lower in heat-treated specimens than in controls. The effects of heat treatment in green wood were similar to those in air-dried wood. (3) The loss tangents of heat-treated specimens were smaller than those of controls at about 0% MC but were larger than those of controls at about 10% MC. We thought that this resulted from the decreased MC at the minimum loss tangent after the heat treatment mentioned above. (4) The properties measured at several MCs were more useful than those at only one moisture content for investigating the effects of heat treatment.This study was presented in part at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 3–5, 1996; and at the 47th annual meeting of the Japan Wood Research Society, Kochi, April 3–5, 1997 相似文献