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采用异氰酸酯(MDI)、E1级中密度纤维板用脲醛树脂(FU)和E0级中密度纤维板用三聚氰胺改性脲醛树脂(MUF)制备难燃中密度纤维板,考察不同类型胶黏剂对难燃中密度纤维板阻燃性能的影响。结果显示,3种胶黏剂制备的难燃中密度纤维板的阻燃性能均达到了GB 8624—2012《建筑材料及制品燃烧性能分级》中B1级要求,MUF难燃中密度纤维板中三聚氰胺的存在对阻燃性能有提升作用,而MDI难燃中密度纤维板中MDI的易燃性降低了中密度纤维板的阻燃性能。 相似文献
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我国中密度纤维板生产能力区域发展现状 总被引:3,自引:1,他引:2
我国已经是世界中密度纤维板第1生产大国,但中密度纤维板生产能力在我国的分布却不均衡,随着我国现阶段中密度纤维板行业的快速发展,不同区域的中密度纤维板生产能力的建设情况也各不相同. 相似文献
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浅析我国中密度纤维板生产企业发展方向 总被引:4,自引:1,他引:3
介绍我国中密度纤维板的发展历程、应用市场;阐述现阶段我国中密度纤维板生产存在的问题;分析我国中密度纤维板生产企业的发展方向. 相似文献
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中国林产工业协会纤维板专业委员会秘书处 《中国人造板》2003,(4)
2002年度中国中密度纤维板生产出现巨大变化。1 生产能力 1982年我国首条中密度纤维板生产线建成投产。 截止2001年底,整整20年中全国已建成投产的中密度纤维板生产线292条,生产能力为年产825.9万m3,(2001年全国中密度纤维板实际产量为527.35 相似文献
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介绍我国中密度纤维板成套设备制造的发展历程及其制造企业创新的艰辛,分析我国中密度纤维板设备制造行业的格局并预测其发展,思考我国中密度纤维板设备制造行业的未来。 相似文献
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Zusammenfassung Die Formaldehydabgabe von MDF mit unterschiedlichen Rohdichteprofilen wurde untersucht. Bei gleichem Formaldehydgehalt gaben
MDF mit hoher Deckschichtrohdicte bei den Untersuchungen in der 1 m3-Prüfkammer nur etwa halb so viel Formaldehyd ab wie MDF mit niedriger Deckschichtrohdichte
Formaldehyde emission of MDF in dependence of density profile
The formaldehyde release of MDF with different density profiles was investigated. Referring to the same formaldehyde content MDF with high surface density emit about half of the formaldehyde as MDF with low surface density.相似文献
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采用强酸工艺制脲醛树脂胶,F/U=1.13,不加三聚氰胺,制得18 mm中密度纤维板的甲醛释放量远低于GB/T 11718-2009要求。因此采用强酸工艺,是实现降低脲醛树脂胶制中密度纤维板甲醛释放量的有效途径。 相似文献
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Medium density fibreboards (MDF) were made from thermomechanical (TMP) and chemo-thermo-mechanical pulps (CTMP) derived from pine wood. As a binder a melamine reinforced urea formaldehyde resin (UF-resin) and diisocyanate polymers (PMDI) were applied. The mechanical-technical properties of the boards as well as some of their chemical properties were evaluated. The results of the investigation led to the following conclusions: MDF from CTMP showed in general higher mechanical properties (bending strength) compared to MDF from TMP. Moreover, the formaldehyde release of the CTMP-boards was lower. This may be due to the formaldehyde scavenging properties of the used pulping chemicals during the process of CTMP. MDF from CTMP showed much higher release of acetic acid compared to MDF from TMP. This is likely to higher deacetylation of the wood substance during CTMP process compared to the TMP technique. 相似文献
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Fibres obtained by the TMP- and CTMP-process from old oak (200–250 years) contain higher amounts of cold water extractives than those obtained from young oak (20–30 years). Moreover, water soluble extractives from old oak fibres are, in general, more reactive towards formaldehyde. This result supports the finding that medium density fibreboards (MDF) made from fibres of old oak emit less formaldehyde than MDF from young oak. 相似文献
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探讨了中密度纤维板生产中的脲醛树脂合成工艺和改性技术,介绍了降低甲醛释放量和施胶量的实用措施。 相似文献
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Chemische Eigenschaften von TMP und CTMP, hergestellt aus Kiefernholz und UF-Harz-gebundenen mitteldichten
Faserplatten (MDF) 总被引:1,自引:1,他引:0
Thermo-mechanical (TMP) and chemo-thermo-mechanical pulps (CTMP) were prepared from pine wood and
from UF-bonded MDF made from pine wood. For preparing TMP pine chips as well as UF-bonded MDF were digested
under pressure at 170 °C. Thereafter, the digested chips and MDF were defibrated at 170 °C
using a single disc refiner. CTMP was prepared from pine wood with 0.25% NaOH (based on dry wood)
under the conditions set forth above. CTMP was also made from MDF under two conditions using 0.15% sodium
hydroxide (% based on dry MDF) and a mixture of sodium sulphite (1%) and sodium hydroxide (0.25%).
The pulps show distinct differences in their properties: TMP from UF-bonded MDF shows lower extractive
content in cold and hot water, lower pH-value and higher buffering capacity towards alkali of the cold water
extractives than the CTMP counterpart. Moreover, CTMP prepared by using sodium hydroxide alone as a pulping
agent increases the content of formate and acetate ions in the cold water extractives. The use of a mixture
of sodium sulfite and sodium hydroxide as a pulping agent decreases, however, significantly the content
of formate and acetate ions in the cold water extractives. This may be due to the buffering action of sodium
sulfite. In general, CTMP decreases the formaldehyde release of the fibres, as measured by the flask method.
In presence of sodium sulfite as a pulping agent for recycled MDF, the formaldehyde release is slashed
to almost 30% of its original value. The formaldehyde release of CTMP from UF-bonded boards seems to be
in the same range as that of TMP from virgin wood.
相似文献
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Medium density fibreboards (MDF) were made from beech in laboratory and pilot plant scale from thermo-mechanical (TMP) and chemo-thermo-mechanical pulps (CTMP) using both melamine reinforced urea-formaldehyde resin (UF-resin) and diphenylmethane diisocyanate polymers (PMDI). The physicalmechanical and chemical properties of the boards were evaluated. From the results the following conclusions can be drawn:
- Both TMP and CTMP led, on using UF-resin, to MDF with very high mechanical properties exceeding the required values in European standards.
- Pulping temperature seems to have an influence on the mechanical properties of the boards, prepared from TMP and CTMP. Increasing the pulping temperature from 150°C to 170°C negatively affects the mechanical board properties, whereas the properties of MDF from CTMP (sulfonic group content between 0.2% and 0.3%) increases by elevating the maximum pulping temperature from 150°C to 170°C.
- The pulping chemicals in the CTMP-process (Na2SO3 and/or NaOH) decrease the formaldehyde release from the boards, as they act as scavengers for formaldehyde.
- Due to higher deacetylation degree during CTMP process, MDF made from CTMP release more than 4 times acetic acid than MDF from TMP. The release of formic acid is quite different, it is in MDF, made from TMP higher than in MDF from CTMP.
- MDF with very high mechanical properties can also be made from beech pulps (TMP) using PMDI. PMDI in combination with a formaldehyde scavenger in the middle layer and UF-resin in the surface layer leads to boards with very low formaldehyde release.
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Andreas Kandelbauer Primoz Petek Sergej Medved Antonio Pizzi Alfred Teischinger 《Holz als Roh- und Werkstoff》2010,68(1):63-75
The decorative laminates industry is a highly competitive industrial sector. To be profitable, manufacturers of impregnated papers for surface laminated MDF and particleboards need to significantly reduce their production costs. Melamine formaldehyde resin (MF) formulations are commonly used for impregnation and coating of such papers, melamine being an important, but costly raw material used in high quantities. While MF is substituted by cheaper urea formaldehyde resins (UF) in the core impregnation, for paper surface films pure MF is used. Therefore, a further reduction in cost could be achieved if a portion of the melamine in the surface film was replaced by urea. In the present contribution, recent results of technological tests on paper laminates using a novel melamine–urea–formaldehyde resin (MUF) formulation are reported and their performance is compared to traditional surfaces made from MF. 相似文献