Densification of in situ prepared mesocarbon microbead/carbon nanotube composites by hot-press sintering
(1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China;
2. Key Laboratory for Advanced Materials Processing Technology of Ministry of Education,
Tsinghua University, Beijing 100084, China;
3. State Key Laboratory of Chemical Resource Engineering,
Beijing University of Chemical Technology, Beijing 100029, China)
2. Key Laboratory for Advanced Materials Processing Technology of Ministry of Education,
Tsinghua University, Beijing 100084, China;
3. State Key Laboratory of Chemical Resource Engineering,
Beijing University of Chemical Technology, Beijing 100029, China)
Abstract: In situ prepared mesocarbon microbead/carbon nanotube(MCMB/CNT) composites are potential precursors of high density carbon materials for various applications. Integrated MCMB/CNT composites were successfully fabricated by hot-press sintering at 550 ℃ under 30 MPa. After further calcination at 900 ℃, the hot-press sintering fabricated MCMB block has an apparent density of 1.77 g/cm3 and the open porosity 5.1%. With the addition of 5%(mass fraction) CNTs, the density of the composite block is elevated to 1.84 g/cm3, and its open porosity is reduced to 3.5%. The flexural strength of composite block with 5% CNTs is elevated to 116 MPa. Through the hot-press sintering, pores of 10−50 nm in the calcinated bulks are remarkably eliminated. The interstice between microbeads in the composite blocks is filled up by CNTs together with β-resin and quinoline-insoluble spheres, which can further contribute to the densification.
Key words: carbon nanotube; mesocarbon microbead; carbonaceous mesophase; flexural strength; density; open porosity