9. Systems with functionality greater than 2. Freezing point

The systems studied in this section involve AA + BB + RA _f or AB + AB + RAf + RB _{f '} , in which f and f ′ are greater than two, and lead to the formation of networks characterized by branches and bridges between chains.

The formation of these networks is characterized by the appearance of two phases in the reaction medium:

• the gel phase, consisting of an infinite network swollen by the solvent ;

• the sol phase, which contains the soluble polymer.

Frost increases at the expense of the soil. Frost occurs at a critical value p _c of p, which corresponds to the frost point and is called the critical degree of advancement....