以木质素磺酸钙为原料,部分替代苯酚,合成具有良好水溶性的木质素改性酚醛树脂( LPF),并在其合成过程中将催化剂前驱体六水硝酸镍(NNH)加入到LPF体系中制备出硝酸镍复合木质素改性酚醛树脂(NLPF),经200°C×24 h固化后,于还原气氛下经800°C×3 h、1000°C×3 h、1200°C×3 h炭化处理,制得NLPF热解炭。探讨催化剂Ni在NLPF复合体系中的分散性,采用X射线衍射仪、激光拉曼光谱仪、场发射扫描电子显微镜、高分辨透射电子显微镜分析NLPF热解炭的晶体结构及显微结构。结果表明,催化剂Ni均匀分散在NLPF复合体系中；NLPF热解过程中NNH被还原成单质Ni,其催化作用使热解炭中生成了结晶程度高的直线型碳纳米管,且呈网状相互交织,均匀的排布在热解炭气孔中；随着NNH添加量的增加,NLPF热解炭的石墨化程度提高,碳纳米管的生成量和直径增加；升高炭化温度同样可以增加碳纳米管的生成量,并使其长度增长。
Calcium lignosulfonate-phenol-formaldehyde resin ( LPF) was prepared by the polymerization of a mixture of calcium lignosulfonate and phenol with formaldehyde using a NaOH catalyst. Nickel nitrate was used as a catalyst for the carbon formation and was added to the LPF before dehydration and curing. The LPF was carbonized at 800, 1 000 and 1 200 ℃ for 3 h. The disper-sion of the catalyst ( Ni) in the cured LPF and the microstructure of the carbon were investigated by SEM, HR-TEM, XRD and Ra-man spectroscopy. Results show that Ni is dispersed homogeneously in the LPF. The carbon is a kind of foam with closed cells. The metallic Ni in the carbon catalyzes the formation of carbon nanotubes that extend from the carbon matrix into the closed cells. The number and length of the carbon nanotubes increase and their crystallinity is improved with increasing carbonization temperature and/or the amount of nickel nitrate added.
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