8. Glossary

Primer

The initiation stage corresponds to the reaction of an A molecule, called an "initiator", which, under the effect of an energy input (light, heat, etc.) reacts (as A or rather in the form of fragments such as free radicals) with a monomer to initiate a polymerization chain reaction.

Molecular extinction coefficient

Absorption coefficient for a unit concentration of absorbing substance and a unit thickness defined by the rate of transmitted light (typically mole ^-1 .l.cm ^-1 ).

Planck constant

Constant that relates the energy of a photon to its frequency; it is 6.626 070 04 x 10 ^-34 m ² ...