A survey of ESR in heat treated carbon blacks

✍ Scribed by G.M Arnold

• Publisher: Elsevier Science
• Year: 1967
• Tongue: English
• Weight: 880 KB
• Volume: 5
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(67)90103-0

✦ Synopsis

The electron spin resonance has been studied for a representative group of variously heat treated carbon blacks using a 3-cm spectrometer equipped with a variable temperature dewar in the cavity. X-ray measurements were made to determine the layer plane spacing and crystallite size. The results show the existence of a relation between the g-value of the ESR line and the layer plane spacing (crystallite size). In general, the g-value remains near the free electron value for small crystallites with turbostratic stacking and increases with crystallite size (either looking at a given carbon black at increasing heat-treatment temperature or in comparing a series of carbon blacks with various particle sizes at the same HTT) up to a value of g=2.017 for the largest highly heat treated material such as Thermax. By checking the temperature dependence of the ESR integrated intensity and correcting for the depression of the g-value caused by the presence of localized spin centers, the true relation between Ag and the interlayer spacing d was obtained.