由椴木木粉和酚醛树脂制备木材陶瓷的研究

以椴木木粉和酚醛树脂为原料制成一种新的木材陶瓷.用TGA、XRlD和SEM技术分别对木材陶瓷的形成机理、物相构成和微观结构进行了表征与研究.详细讨论了碳化温度和酚醛树脂用量对木材陶瓷显气孔率、体积电阻率和弯曲强度的影响.结果表明,木材陶瓷是由酚醛树脂生成的玻璃态的硬碳和由木粉生成的无定形的软碳组成的多孔性碳复合材料;随碳化温度升高或酚醛树脂用量的增加,木材陶瓷的显气孔率和弯曲强度增大,体积电阻率下降;碳化温度升高可以使(002)衍射峰逐渐变窄,强度增大,并且向高角度移动,晶面间距d₍₀₀₂₎减小,而酚醛树脂用量的增加对(002)衍射峰和晶面间距d₍₀₀₂₎基本没有影响;当碳化温度为1350℃,酚醛树脂用量为160wt％时,木材陶瓷的显气孔率、体积电阻率和弯曲强度分别达到了50％、2.0×10^-2Ω·cm和25MPa.

Woodceramics Prepared from Basswood Powder and Phenolic Resin

A new woodceramics was fabricated from basswood powder and phenolic resin. Thermogravimetric analysis (TGA) was applied to reveal the pyrolysis behaviors of wood powder and phenolic resin. Scanning electron microscope (SEM) and X-ray diffraction (XRD) were employed to characterize and analyze the microstructures and phase identification of woodceramics. The effects of carbonization temperature and content of phenolic resin on the apparent porosity, volume electrical resistivity and bending strength of woodceramics were discussed, respectively. The results show that woodceramics is a kind of composite of porous amorphous carbon from wood powder and glassy carbon from phenolic resin, and is not composed of a completely graphitized carbon structure but has a turbostratic structure. With the increase in the carbonization temperature, apparent porosity and bending strength increase, while volume electrical resistivity decreases, the broad (002) peak gradually becomes sharper, and the (002) interplanar spacing becomes smaller. However, when content of phenolic resin increases, no detectable changes of the broad (002) peak and the (002) interplanar spacing take place. The apparent porosity, bending strength, and volume electrical resistivity of woodceramics prepared from wood powder/ phenolic resin composite in a ratio of 100:160 by weight carbonized at 1350℃ are about 50%, 25MPa, and 2.0×10^-2Ω·cm, respectively.