18. Glossary

transition vitreuse; glass transition

Temperature at which an undercooled liquid becomes rigid. It is manifested by a specific heat jump in calorimetry and a viscosity of the order of 10 ¹³ Po.

DSC (Differential Scanning Calorimetry)

Common calorimetric technique for locating thermal events and the energies involved.

relaxation : relaxation

A type of molecular mobility involving thermal activation to overcome an energy barrier, as opposed to vibration.

Arrhenius law

Law describing the temperature-dependent evolution of a relaxation process or viscosity, when the energy barrier E does not vary with temperature (equation