Hlatshwayo, S.R.Focke, Walter WilhelmRamjee, ShatishRand, BrianManyala, Ncholu I.2012-12-122012-12-122013-01S.R. Hlatshwayo, W.W. Focke, S. Ramjee, B. Rand, N. Manyala, Rheological behavior and thermal properties of pitch/poly(vinyl chloride) blends, Carbon, vol 51, pp. 64-71 (2013), doi: 10.1016/j.carbon.2012.08.0120008-6223 (print)1873-3891 (online)10.1016/j.carbon.2012.08.012http://hdl.handle.net/2263/20741The effect of adding poly(vinyl chloride) (PVC) and coke filler on the rheological behavior and thermal properties of a coal tar pitch was investigated with a view to developing an appropriate viscoelastic binder for the injection molding of graphite components. Dynamic mechanical analysis revealed that the pitch formed compatible blends with PVC featuring a single glass transition temperature (Tg) intermediate to the two parent Tg’s. Adding PVC to the pitch increased melt viscosity substantially and resulted in strong shear thinning behavior at high PVC addition levels. Adding coke powder as filler increased the melt viscosity even further and enhanced shear thinning trends. Pyrolysis conducted in a nitrogen atmosphere revealed interactions between the PVC and pitch degradation pathways: the blends underwent significant thermal decomposition at lower temperatures but showed enhanced carbon yields at high temperatures. Pyrolytic carbon yield at 1000 C was further improved by a heat treatment (temperature scanned to 400 C) in air or oxygen. However, carbon yield decreased with addition of PVC. In addition, the degree of ordering attained following a 1 h heat treatment at 2400 C also decreased with increasing PVC content.en© 2012 Elsevier. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in Carbon. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Carbon, vol 51, January 2013, doi: 10.1016/j.carbon.2012.08.012.Rheological behaviorPVCCoke fillerCoal tar pitchCoal-tar products -- Thermal propertiesFillers (Materials) -- Thermal propertiesPitchCokePolyvinyl chlorideRheologyViscoelastic materialsViscoelasticityPostprint Article