ABSTRACT
Foaming polymers involves materials in various phases, states, and changes between states and phases. In general, the changes are from stable state to unstable state, then to another stable state. Thermodynamics and kinetics become two fundamental principles governing the changes. The former defines the ultimate system conditions we can accomplish, and the latter shows the rate process to reach the conditions. Basically, they go hand in hand. It is of vital importance to understand thermodynamics and kinetics, before we investigate engineering and processing parameters.
