ASTM D4591 defines conditions for the use of differential scanning calorimetry (DSC) with fluoropolymers including PTFE, PVDF, PCTFE, PVF and their copolymers. The standard specimen mass is 9-10 mg weighed to 0.01 mg accuracy with standard heating/cooling rates of 10°C/min.
DSC analysis can: identify fluoropolymers by transition temperatures, compare crystalline content by measuring heat of fusion, characterize PTFE morphology and molecular structure from first-heat thermal curves, and supplement standard specific gravity testing.
The procedure places the specimen in an aluminum DSC pan, heats from the start temperature through the melt transition, then cools to measure crystallization. This is referenced by AS4373 Method 813 for evaluating PTFE insulation sinter state on aerospace wire.