Properties of ethylene vinyl acetate copolymers (EVA) are determined by the vinyl acetate (VAC) content of EVA. Very often it is necessary to know the VAC content of the EVA rubber. The integrated TGA-FTIR-System is used to analyze uncured and vulcanized EVA types with different VAG content. A sample of raw EVA is analyzed to show which results one can get with this integrated analytical system. Several EVA types with VAC contents in the range between 40% and 70% are analyzed to decide whether a distinction is possible.