C-60 fullerene polymers
UNSPECIFIED (2003) C-60 fullerene polymers. In: NATO Advanced Research Workshop on Nanostructured Materials and Coatings for Biomedical and Sensor Applications, KIEV, UKRAINE, AUG 04-08, 2002. Published in: NANOSTRUCTURED MATERIALS AND COATINGS FOR BIOMEDICAL AND SENSOR APPLICATIONS, 102 pp. 239-248.Full text not available from this repository.
TEM investigations were performed on high temperature and pressure C-60 fullerene. A mixed phase of alternating rhombohedral lamellae and tetragonal,domains is formed. At higher temperatures 900-1173 K graphitic 'hard' carbon phases formed, via an inter-polymer interface instability and/or shear mechanism. This phase exhibited a hardness of 10-15 GPa and a high degree of elastic recovery under indentation. The kinetics of graphitisation were slow and proceeded via cross-linked intermediates, which influenced the hardness markedly, up to 33.5 GPa. In-situ investigations into the P/T field Of C60 were performed using energy dispersive X-Ray diffraction techniques. The P/T history and pressure isotropy were investigated to confirm and optimise conditions for 3-D polymer formation. Formation of 3-D polymers has been carried out in-situ, however the reclaimed sample failed to live up to hardness expectations, due to depolymerisation problems on pressure release. Isotropy in the pressure field promoted formation and retention of the 3-D FCC structure. The existence of a series of ferromagnetic rhombohedral C60 polymers has been realised. This property has been shown to occur over a range of preparation temperatures at 9 GPa. The structure is shown to be crystalline in nature containing whole undamaged Buckyballs. Formation of radicals is most likely due to thermally activated shearing of the bridging bond resulting in dangling bond formation.
|Item Type:||Conference Item (UNSPECIFIED)|
|Subjects:||Q Science > QD Chemistry
Q Science > QA Mathematics
Q Science > QC Physics
|Series Name:||NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY|
|Journal or Publication Title:||NANOSTRUCTURED MATERIALS AND COATINGS FOR BIOMEDICAL AND SENSOR APPLICATIONS|
|Editor:||Gogotsi, YG and Uvarova, IV|
|Number of Pages:||10|
|Page Range:||pp. 239-248|
|Title of Event:||NATO Advanced Research Workshop on Nanostructured Materials and Coatings for Biomedical and Sensor Applications|
|Location of Event:||KIEV, UKRAINE|
|Date(s) of Event:||AUG 04-08, 2002|
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