Calorimetría diferencial de barrido (DSC)

La calorimetría diferencial de barrido (DSC, por sus siglas en inglés, “Differential

Scanning Calorimetry”) mide las diferencias entre la cantidad de calor absorbido o desprendido

entre una muestra y otra de referencia inerte en función de la temperatura, cuando ambas se someten a un calentamiento o enfriamiento, generalmente a velocidad constante. Esta técnica permite estudiar fenómenos exotérmicos y endotérmicos en polímeros y es capaz de diferenciar algunas de las transiciones térmicas más importantes, como una transición vítrea, una cristalización o una fusión.

La transición vítrea de un polímero se observa como un cambio en la pendiente del flujo de calor en un barrido de temperaturas (Figura 5.3). La temperatura de transición vítrea se determina como el punto medio entre las dos pendientes. La cristalización se determina como un pico y la fusión como un valle.

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Figura 2.3- Esquema de un termograma típico para materiales elastóméricos.

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