Thermodynamics of radical polymerization

These conditions favor the formation of polymer, but it is obvious from the general treatment of the energetics of the reaction that the chain length decreases as the temperature rises. This can be understood if we postulate the existence of a depolymerization reaction. 

When the temperature increases, the depolymraization reaction becomes more important, and AGp becomes less negative. Eventually, a tranperature is reached at which AGp = 0, and the overall rate of polymerization is zero. This temperature is known as the ceiling temperature T.  

If both the forward and reverse reactions arc treated as chain reactions, then 

The thermodynamic significance of can be related to this kinetic analysis by using the Arrhenius expressions for the rate constants. At equilibrium 

By rearranging and considering equilibrium conditions it follows that 

---

Kinetics and Thermodynamics of Radical Polymerization Thus, eqn (1.53) becomes... 

---