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木陶瓷的制造(Ⅰ)——实木陶瓷 总被引：9，自引：4，他引：9
以大青杨（Populus ussuriensis)木材为原料，浸渍酚醛树脂后经800℃隔氧烧结，制得实木陶瓷，分析了样品在质量和体积上的变化。研究发现，试样经过高温烧结后，相对酚醛树脂处理前，后绝干试样的炭得率，体积剩余及木陶瓷产品密度与树脂质量分数呈正相关，树脂处理使木材样品炭化时弦、径、纵向收缩差异减小。 相似文献
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将原子力显微镜技术应用于木陶瓷分析,观测了大青杨木材和酚醛树脂炭化前后样品表面的微观形态.结果表明,通过原子力显微镜技术,可以清晰地观察到大青杨木材表面呈波纹状排列有序的纤维物质,波纹峰谷间水平距离390.63nm,垂直距离14.745nm.炭化后该结构消失,样品的粗糙度大大增加,均方根粗糙度由炭化前的4.487nm增加到炭化后的68.147nm.未炭化酚醛树脂因固化时水分的逸出,留下类似火山口状的峰谷,谷宽437.60nm,谷深22.202nm.炭化后该结构完全消失,样品的均方根粗糙度由炭化前的4.612nm增加到50.446nm. 相似文献
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Woodceramics (WCS) are new porous carbon materials that have been shown to possess many excellent properties, but the chemical
mechanism during pyrolysis has not been reported yet. In order to investigate this process, pyrolysis of medium density fiberboard
(MDF) was analyzed by thermogravimetry coupled with Fourier transform infrared spectroscopy (TG-FTIR) in this study. The results
showed that the pyrolysis consisted of three stages up to 700°C. The first stage of the pyrolysis occurred below 240.0°C and
was mainly due to moisture evaporation. The second stage between 240.0° and 390.2°C accompanied the main mass loss. The maximum
pyrolysis speed (mass loss) was about 3.79% per minute at 313.2°C. This was believed to coincide with the cleavage of ether
bridges between the wood material and phenol-formaldehyde (PF) resin, and pyrolysis of carbohydrate. At higher temperature,
the pyrolysis of PF resin and lignin was the main reason for the mass loss in the third stage. The microcosmic environments
of both the MDF and PF resin in the MDF treated with PF resin were different from the untreated MDF and PF resin, so that
the temperatures at which their pyrolysis occurred and the quantities of evolved gases were different. During the process
of WCS preparation, the rate of temperature increase should be very slow before it reaches 700°C, especially at around 313.2°C,
at which point violent pyrolysis occurs. Such temperature control should allow uniform sintering of the sample and should
reduce flaws in the product. 相似文献
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Effects of microwave irradiation on the basic properties of woodceramics made from carbonized tobacco stems impregnated with phenolic resin 总被引：2，自引：1，他引：1
Wei Li Libo Zhang Jinhui Peng Ning Li Shimin Zhang Shenghui Guo 《Industrial Crops and Products》2008,28(2):143-154
A series of woodceramics derived from carbonized tobacco stems and phenolic resin composite heated by microwave irradiation was prepared and effects of microwave irradiation time, power and mass fraction of phenolic resin in woodceramics on the mass loss ratio, volume shrinkage ratio, apparent density, open porosity and volume electrical resistivity were investigated systematically. The pyrolysis behaviours of tobacco stems, phenolic resin and carbonized tobacco stems/phenolic resin composite were also evaluated using thermogravimetry. The experimental results showed that the mass loss ratio, volume shrinkage ratio and apparent density increased, while the volume electrical resistivity and open porosity decreased with increasing microwave irradiation time. The apparent density increased, while the mass loss ratio, volume shrinkage ratio, volume electrical resistivity and open porosity decreased with an increase in the mass fraction of phenolic resin. The mass loss ratio, volume shrinkage ratio and open porosity increased, while apparent density and volume electrical resistivity decreased with an increase in the microwave power. Microstructures of woodceramics obtained at various microwave irradiation time were characterized by scanning electron microscopy (SEM) technique, which confirmed the results of pyrolysis analyses of samples and effects of microwave irradiation on basic properties of woodceramics prepared. 相似文献
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[目的]以玉米秸秆为原料,以酚醛树脂为胶黏剂制备一种新型的木陶瓷。[方法]研究碳化温度和酚醛树脂用量对木陶瓷得碳率、显气孔率、弯曲强度和耐磨性的影响。[结果]所得材料是由玉米秸秆生成的无定形软碳和酚醛树脂生成的玻璃态硬碳组成的多孔性复合材料。随着碳化温度的升高,材料的显气孔率、弯曲强度和耐磨性增强,得碳率下降;随着酚醛树脂用量的增加,得碳率、显气孔率和耐磨性能提高。[结论]该研究为玉米秸秆的综合利用提供了新途径。 相似文献
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以工业木质素为原料制造新型多孔炭材料木陶瓷,并对产品得率、强度及微观结构形态进行了研究。结果表明,随着酚醛树脂用量的增加,木质素陶瓷的质量得率和体积得率略有增加,抗弯强度大大提高,抗压强度也提高明显。当木质素与酚醛树脂质量比为1．33∶1时,木质素陶瓷的抗弯强度为1．88MPa,抗压强度达3．86kN/cm~2。微观结构分析表明,在木质素—酚醛树脂复合板中有团块状木质素夹杂出现,高温烧结后样品孔隙结构增多。高温烧结前后样品的比表面积分别为0．2448m~2/g和0．9742m~2/g。 相似文献
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