煤沥青乳液制备中间相炭微球.pdf

材料工程/2010年3期
硅油/煤沥青乳液制备中间相炭微球
Preparation of Mesocarbon Microbeads with Silicone
Oil/Pitch Emulsion
程有亮,李铁虎,李凤娟,庄强,经德齐,赵廷凯
(西北工业大学材料学院,西安710072
CHENG You-liang, LI Tiehu, LI Feng-juan,
ZHUANG Qiang, JING De-qi, ZHAO Ting-kai
( School of Materials Science, Northwestern Polytechnical University, Xi'an 710072, China)
摘要:以中温煤沥青为原料,耐高温油为分散剂和导热介质,通过在反应崟中混合形成硅油/煤沥青乳液来制备中间
相炭微球( Mesocarbon Microbeads,MCMB)。利用SEM、激光粒度仪和XRD分析等,研究了硅油用量对MCMB形成的
影响。结果表明:硅油添加量对MCMB的形成有重要影响,当加人少量硅油后,MCMB粒径显著减小,分布均匀,小球
表面较光滑,粘结现象减少,微晶结构得到改善,但四氢呋喃不溶物(THFI)收率降低。增加硅油用量,MCMB的粒径大
小和微晶结构变化不大,小球之间粘结少,THFI收率增加,但小球表面附着小颗粒。当硅油/煤沥青的质量比为3:
时,可得到粒径分布窄,Dse为0.82um,表面比较光滑,收率为8.2%的MCMB
关鍵词:煤沥青;热聚合;中间相炭微球;硅油/煤沥青乳液
中图分类号:TQ127.1文献标识码
文章编号:1001-4381(2010)030056-04
Abstract: Mesocarbon Microbeads(MCMB)were prepared by heat condensation in the retort with
coal tar pitch and silicone oil as the dispersion and heat exchange medium. The influence of silicone oil
on the preparation of MCMB was studied by SEM, laser particle size analyzer and XRD. The results
showed that silicone oil content had an important influence on the formation of MCMB. After the ad
dition of silicone oil, the spheres with uniform distribution and smooth surface had smaller diameter
nd better crystallite structure. At the same time, the yield of THFI and surface adhesion between
spheres decreased. With increasing silicone oil content, the diameter and crystallite structure of the
spheres were hardly changed. The spheres presented better dispersion and the yield increased, while
some small particles attached to the surface of MCMB. When the ration of silicon oil/pitch was 3: 1
MCMB with uniform size distribution and smooth surface were obtained. D,o of MCMB was 0.82 m,
and the yield of THFI was 8.2%
Key words: coal tar pitch; heat condensation; MCMB; silicone oil/pitch emulsion
1973年 Honda和 Yamada首先通过沥青聚合得
MCMB通常采用的制备方法有缩聚法们、乳化
到中间相炭微球,自此对MCMB的研究有了很大的法和悬浮法?。其中缩聚法制备MCMB,产率低、
进步。含有稠环芳烃的化合物(如煤沥青、石油沥球径分布宽、球形度不理想、小球表面常附着不溶物,
青、滎等)在热处理时,通过热缔疑反应发生中间相转限制了MCMB的应用;乳化法生产工艺复杂,在制备
变,形成一种向列液晶结构,由于表面张力作用聚合物过程中存在困难;悬浮法使用了表面活性剂,虽能政善
呈球形,把这些各向异性的小球体从各向同性的母体MCMB的分散性,但同乳化法一样,工艺条件控制难
中分离出来得到的产物就称为MCMB28。MCMB度大,这地不利于MCMB的制备;而且乳化法和悬浮
具有良好的化学稳定性,热稳定性,导电和导热性法首先要生成中间相沥青,然后以中相沥青为原料
等],被认为是制备高性能炭材料的优质前驱体部,广来形成乳液或悬浮液来得到MCMB
泛应用于制备高强高密CC复合材料、锂离子二次电
本工作用高温硅油与原料煤沥青先形成悬浮液,然
池负极材料、高性能液相色谱柱填料、催化剂载体和高后在高于煤沥青软化点的温度下,通过搅拌使悬浮液形
比表面积活性炭等领域
成硅油/煤沥青乳液,再经过热聚合得到MCMB。在此