Practical rubber formulations are complex mixtures of polymer (s), fillers, plasticizers, curatives, and processing aids. Classical methods exist for determining many of the components of these systems but are too time consuming for routine use in quality control or problem solving activities. Thus a need has existed for more rapid procedures. Previous studies of gum, compounded, and cured elastomers showed that thermogravimetry (TG) can provide information regarding the polymer, oil, carbon black, mineral filler, and ash content of vulcanizates. The present study extends this approach to multicomponent polymer and carbon black systems to determine whether components of similar thermal characteristics can be effectively analyzed. Vulcanizates containing binary (natural rubber (NR)/ethylene propylene terpolymer (EPDM) or ternary (NR/EPDM/styrene-butadiene rubber) blends were successfully analyzed by the standard, dynamic TG method.IsothermalTG was shown to have significant potential for analyzing blends of FEF and SRF carbon blacks (CB) in a standard formulation. Two additional approaches, derivative TG (DTG) and normal probability analysis are examined for potential applicability in these analyses. The former has apparent value for polymer blend analysis; the latter, based on preliminary data, may have value in the analysis of some CB blends.