text: Monomers undergoing supramolecular polymerization are considered to be in equilibrium with the growing polymers, and thermodynamic factors therefore dominate the system.  However, when the constituent monomers are connected via strong and multivalent interactions, a "metastable" kinetic state can dominate the polymerization.  An externally supplied energy, in the form of heat in most cases, can transform the "metastable" state into a thermodynamically stable polymer.  A clear understanding of multiple pathways exist in supramolecular polymerization is still under debate, however, the concept of "pathway complexity", introduced by E.W. "Bert" Meijer, shed a light on the kinetic behavior of supramolecular polymerization.  Thereafter, many dedicated scientists are expanding the scope of "pathway complexity" because it can produce a variety of interesting assembled structures from the same monomeric units.  Along this line of kinetically controlled processes, supramolecular polymers having "stimuli-responsive"  and "thermally bisignate" characteristics is also possible.
  In conventional covalent polymerization, two models based on step-growth and chain-growth mechanisms are operative.  Nowadays, a similar subdivision is acceptable for supramolecular polymerization; isodesmic also known as equal-K model (step-growth mechanism) and cooperative or nucleation-elongation model (chain-growth mechanism).  A third category is seeded supramolecular polymerization, which can be considered as a special case of chain-growth mechanism.