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1.
用CONE法研究木材阻燃剂FRW的阻燃机理 总被引：11，自引：1，他引：11
采用锥形量热仪(CONE)法对复合木材阻燃剂FRW处理紫椴木材(FZ)、FRW的组分磷酸脒基脲(GUP)处理紫椴木材(GZ)、硼酸处理紫椴木材(BZ)和未处理的紫椴木材(UZ)的燃烧性进行了系统的测定，通过对上述试样在燃烧时的热释放、质量变化、烟气产生以及尾气成分等实验数据的综合对比分析，讨论了阻燃剂的作用机理。结果表明：1)FRW阻燃剂显著降低了木材的热释放速率(RHR)、总热释放量(1FHR)、有效燃烧热(EHC)、质量损失速率(MLR)、烟比率(SR)、比消光面积(SEA)、CO2的浓度及产率(Yco2)；2)GUP与硼酸之间存在显著的阻燃协同效应；3)FRW阻燃木材的MLR曲线与RHR曲线相似，失重和热释放主要发生在有焰燃烧阶段；4)FRW阻燃处理能显著提高木材燃烧时的成炭率，说明催化成炭是FRW阻燃机理的主要方面。 相似文献
2.
阻燃处理马尾松的热动力学分析 总被引：3，自引：0，他引：3
将硼酸、硼砂混合制成均匀的阻燃剂，并以脲醛预缩液为载体，采用动态热重法来分析马尾松木材阻燃处理前后的热动力学特性。经定性与定量分析，结果表明，该阻燃体系能使松木的热解温度降低；平均热解失重率降低、失重过程变缓；产炭量增加，在炭化阶段的失重减少。 相似文献
3.
用FTIR法研究木材阻燃剂FRW的阻燃机理 总被引：3，自引：0，他引：3
采用FTIR显微分析技术,对FRW阻燃处理红松木材限制燃烧固相产物的结构进行分析;采用GC_FTIR联机分析方法,对经FRW阻燃剂及其主要组分处理的紫椴木材试样的热解挥发性产物进行分析和鉴定;讨论FRW阻燃处理木材的热解炭化过程、阻燃剂的作用以及热解产物的结构特点。结果表明:FRW阻燃木材受热时,随着温度的升高,在FRW及其分解产物的催化下,木材逐步发生聚糖脱水、半纤维素脱乙酸、聚糖降解、木质素降解、木材热解产物聚合、脂肪族聚合物脱氧及芳构化等反应,最终炭化;FRW阻燃剂改变了木材的热解途径,并且显著降低了挥发性有机化合物的生成量。 相似文献
4.
The structures of the solid state products formed by the partial combustion of Korean pine wood treated with fire-retardant
FRW were analyzed by microscopic FTIR. The volatile pyrolytic products of basswood (Tilia amurensis) specimens treated with FRW and its components guanylurea phosphate and boric acid were analyzed by GC-FTIR. The pyrolytic
and charring process, the effects of fire-retardant, and the structural characteristics of the pyrolytic products were discussed.
It was concluded that upon heating and by the catalysis of FRW and its decomposition products reactions of wood took place
successively, namely the dehydration of polysaccharide, the elimination of acetic acid from hemicellulose, the degradation
of polysaccharide, the degradation of lignin, the polymerization of the pyrolytic products of wood, reactions of oxygen-element-elimination
of aliphatic polymers and the structural change of the latter to form aromatic structures, and charring. The pyrolysis process
of wood was altered and the yield of volatile pyrolytic products was decreased by FRW treatment.
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Translated from Scientia Silvae Sinicae, 2005, 41(4): 149–154 [译自: 林业科学, 2005, 41(4): 149–154] 相似文献
5.
木材阻燃剂FRW的阻燃机理 总被引：10，自引：2，他引：10
在综合分析热分析法、锥形量热仪法和FTIR法获得的FRW阻燃机理研究结果并吸收木材阻燃机理研究现有成果的基础上,推导进而提出了木材阻燃剂FRW的阻燃机理。其主要内容是:1)FRW阻燃木材受热时,阻燃剂FRW分解产生不燃性气体和不挥发的酸性熔融物质,具有降低体系温度和氧气浓度及屏蔽热辐射的作用,降低了木材的热解速度;2)FRW的组分硼酸和GUP的酸性分解产物催化木材脱水、降解,以及木材热解产物的缩合、聚合、芳构化等反应,能改变木材的热解途径并使其向着有利于炭化的方向变化,FRW显著的催化成炭作用,使阻燃木材的燃烧放热量大大降低,这是FRW阻燃机理的主要方面;3)硼酸与GUP起阻燃作用的温度和方式不同,并且有相互补充的作用,因而表现出阻燃协同效应。 相似文献
6.
7.
酚类阻燃剂处理杉木热解过程的热动力学研究 总被引：8，自引：0，他引：8
抗流失阻燃剂是当前阻燃剂研究开发的一个重要方向。采用TG DTA热分析技术研究了酚类阻燃剂处理杉木热解过程各阶段的木炭产量和热动力学参数。结果表明 ,酚类阻燃剂阻燃处理杉木的产炭量因苯环上取代基不同而不同 ,其阻燃作用的大小顺序为 :氨基 >溴 >硝基。同时具有氮元素和溴元素的二溴硝基苯酚和二溴氨基苯酚的产炭量都大于相应的单取代苯酚衍生物。浸泡实验后 ,磷酸氢二铵的产炭损失率是二溴硝基苯酚的 5倍。阻燃处理后产炭量的增大总是对应于炭化阶段热解反应峰温降低、反应速率常数增大 ,但产炭量的增大程度与这些热动力学参数的改变是负相关的。因此 ,氮和溴的苯酚衍生物不仅对木材具有很强的阻燃作用 ,而且具有很强的抗浸泡能力 ,氮元素的阻燃作用与其在阻燃剂中的氧化态关系极大 ,氮和溴在木材阻燃中存在协同增效作用 ,阻燃处理对木材的吸湿性也有影响。 相似文献
8.
Silicic acid: boric acid complexes as wood preservatives 总被引：1，自引：0，他引：1
Haruhiko Yamaguchi 《Wood Science and Technology》2003,37(3-4):287-297
Wood was treated with a low molecular-weight silicic acid: boric acid agent and examined for increased resistance to termites and combustion. Wood treated with silicic acid only exhibited increased termite resistance, but not to the marked extent observed after treatment with a mixture of silicic and boric acids. Increasing the quantity of boric acid also increased the termite mortality rate and shortened the time to death. Oral-toxicity tests using dyed silicic acid: boric acid suggested that the boric acid in the agent acted as a stomach poison. Field tests on stakes over three years showed that even if stakes were placed near the termite exit, those treated with silicic acid and high levels of boric acid had no attack by termites and maintained their original form. Though these specimens were installed in the field during three rainy seasons (about six months in total) in three years, the termite resistance ability of these chemicals was maintained. It became clear that this silicic acid: boric acid agent has a high water resistance ability worthy of application in the outdoors. Combustion tests showed that flame and glowing combustion times were shortened at high levels of boric acid. When a boric acid: methanol solution was added at of rate of not less than 25 ml for 100 g of colloidal silicic acid solution (CSAS), flaming and glowing combustion were not observed. Although the charring length of the wood specimen which was treated with a low molecular weight silicic acid: boric acid agent decreased to 2/3 of that of the control wood, the charring lengths were not influenced by the level of boric acid. However, the volume of smoke decreased relative to the amount of boric acid that had been added. 相似文献
9.
Impregnation and mechanical properties of three softwoods treated with a new fire retardant chemical
Three softwoods, Sugi (Cryptomeria japonica), Korean Pine (Pinus koraiensis) and Hinoki (Chamaecyparis obtusa), were vacuum–pressure impregnated with a fire retardant chemical consisting of ammonium phosphate polymer (APP), guanyl urea phosphate (GUP), phosphonic acid and a minor amount of additives. The variation in impregnation between and within wood species was investigated. A significant relationship and similar trends were found between fire retardant chemical (FR) uptake and specific gravity (SG), as well as void volume filled (VVF) and SG. Moreover, the effects of fire retardant treatment on mechanical properties, including modulus of rupture (MOR), static modulus of elasticity (MOE) and dynamic modulus of elasticity (DMOE), were evaluated. The results indicated that the trend of impregnation and regression function varied between species and positions within the same species. However, the relationship of SG and chemical uptake and that of VVF and chemical uptake could be represented by a positive linear regression, and the trends were similar between wood species. Both of SG and VVF increased with increasing FR uptake. After fire retardant treatment, the MOR and static MOE were reduced compared with before treatment. Conversely, the DMOE increased after treatment. 相似文献
10.
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
11.
热分析法研究磷酸活化法的热解过程 总被引：14，自引：2，他引：12
采用差热天平，对木材和主要分离组分及其添加磷酸混合物的差热曲线和热重曲线进行解析。展示了磷酸法制取活性炭的炭活化过程的热化学变化动态，从热分析上探讨其热解历程。 相似文献
12.
阻燃木材应具备的产品性能 总被引：9，自引：1，他引：8
本文概述了使用阻燃木材的必要性,论述了传统型和第二代木材阻燃剂的主要差别,讨论了阻燃木材应具备的产品性能,特别是难燃性,吸湿性,强度,使用寿命。 相似文献
13.
H. Yamaguchi 《Wood Science and Technology》2002,36(5):399-417
A new wood preservative containing low molecular weight and low-toxicity silicic acid (LWSA) was investigated. To prevent
environmental pollution with the wood preservative, a silicic acid monomer aqueous solution (SAMS) or colloidal silicic acid
solution (CSAS) was combined with various metal compounds or boric acid. Agents where SAMS or CSAS was combined with boric
acid gave good protection against decay caused by the brown-rot fungus Fomitopsis palustris, the treated wood (Cryptomera japonica D. Don) specimens after the leaching test maintained a high resistance to decay. The leaching and decay tests revealed high
quantities of chemicals leaching from wood treated with SAMS-metal agents. However, when wood was treated with SAMS-boric
acid, there was little leaching of agent in either test. The mechanism of resistance of wood, which was treated with boric
acid mixed with CSAS or SAMS, to the brown-rot fungus F. palustris were investigated. When the concentration of boric acid was high, mycelial growth was inhibited completely and no protein
production was detected. When the amount of boric acid was low, the xylanase, mannase and cellulase activities were lower
than with control wood powder. When powdery boric acid was combined with CSAS, it was considered that the treated woods have
higher anti-weather properties than when boric acid-methanol solution was mixed with CSAS. The agent-preparation method adopted
should be considered carefully after taking the treatment process and the intended use of the preservative-treated wood into
account.
Received 26 September 2000
This study was supported by a Grant-in-Aid (09460079) for Scientific Research from the Ministry of Education, Science, and
Culture of Japan. 相似文献
14.
阻燃剂WFRJ1改性木材的体积稳定性和涂饰性能 总被引：3，自引：0，他引：3
用阻燃剂ＷＦＲＪ１处理大青杨木材并对处理材的阻燃性能、涂饰性能和体积稳定性进行测定。结果表明：ＷＦＲＪ１可用于木制品的阻燃处理。当ＷＦＲＪ１浓度为１０％时,氧指数可达到５０％以上,与水溶性ＲＦ树脂复配,可大幅度提高处理材的抗胀缩率和阻湿率,增加体积稳定性。经ＷＦＲＪ１处理后杨木单板的涂饰性能未受影响。 相似文献
15.
16.
The charring rates of 12 different wood species originating from Europe and the tropics with densities ranging from 350 to
750kg/m3 were investigated to obtain clues on their fire resistance behavior. This was done by measuring the thickness of the charred
layer after a 30-min exposure to the standard fire ISO 834-1. No correlation was observed between charring rate and density.
In search of another physical property that could be used as an indicator of fire resistance, the oxygen permeabilities of
the selected wood types were measured. A strong correlation between oxygen permeability perpendicular to the wood fiber direction
and charring rate was found, which is quite straightforward given that oxygen is the necessary component to enable smoldering
and ignition, both affecting the charring rate. It seems that oxygen permeability is potentially more suitable as a parameter
to evaluate the fire resistance of char-sensitive wooden constructions, rather than density. No general preference of the
tree ring orientation from 0° (tangential) to 45° and 90° (radial) was found for these measurements.
The publication of this article was made possible by an Emachu Research Fund. The authors are grateful for the fund. 相似文献
17.
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.
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Translated from Scientia Silvae Sinicae, 2007, 43(12): 117–121 [译自: 林业科学] 相似文献
18.
采用杉木和泡桐为试材,对经过KY-FW阻燃剂处理的木材与未经处理的木材进行对比研究,分析KY-FW阻燃剂对木材力学性能的影响.结果表明,木材经KY-FW阻燃剂处理后,除冲击韧性降低外,其它主要力学性能指标(如抗弯强度、顺纹抗压强度及硬度)都有所提高.KY-FW阻燃木材的力学性能达到了一级水基型阻燃剂标准规定的相应指标. 相似文献
19.
该研究采用BL-阻燃剂溶液浸渍处理杨木单板,比较分析BL-阻燃杨木与未阻燃杨木的吸湿性和尺寸稳定性的影响。结果表明:①在不同的湿度条件下,阻燃处理后试件的吸潮率递增值明显高于未处理材。②BL-阻燃剂浓度越高的试件吸潮率也越高,相同浓度的试件在不同湿度中,湿度越高,其吸潮率也越高。③阻燃后杨木单板的尺寸变化率明显高于未处理材的,BL-阻燃剂具有较高的吸湿性,其对杨木单板尺寸稳定性的影响规律为:厚度弦向径向。 相似文献
20.
利用质轻、松软、强度低、径极小的杉木间伐材，经阻燃液浸渍处理、干燥后，生产阻燃杉木胶合层积材。制出的胶合层积材物理力学性能满足日本农林集成材标准，同时又具有一定的阻燃效果，可供作室内装饰和家具等用材。 相似文献