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Low Field Nuclear Magnetic Resonance of Structural Alterations in Coal Tar Pitch Subjected to Heat Treatment

Luiz de Freitas1, 2, Maria Tavares2 and Ricardo Michel2
Affiliation: 
1Centro Tecnologico do Exercito, Av. das Americas 28705, Guaratiba, 23020-470, Rio de Janeiro, RJ, Brasil 2Instituto de Macromoleculas Prof. Eloisa Mano, Universidade Federal do Rio de Janeiro, CT, Bloco J, Ilha do Fundao, 21941-972, Rio de Janeiro, RJ, Brasil
DOI: 
https://doi.org/10.23939/chcht05.02.221
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Keywords:

Abstract: 
Development of anisotropy in tar pitches under heat treatment was measured by hot centrifugation and by low field NMR technique through the spin-lattice relaxation time of the hydrogen nucleus (T1H). By using a double exponential model for T1H calculations it was possible to quantify the size of the isotropic and anisotropic domains, suggesting that low field NMR is a suitable technique to address anisotropy in pitches.
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