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Depolymerization is a very common process. Digestion of food involves depolymerization of macromolecules, such as proteins.It is relevant to polymer recycling.Sometimes the depolymerization is well behaved, and clean monomers can be reclaimed and reused for making new plastic.
A key physical factor which distinguishes the LCST from other mixture behavior is that the LCST phase separation is driven by unfavorable entropy of mixing. [18] Since mixing of the two phases is spontaneous below the LCST and not above, the Gibbs free energy change (ΔG) for the mixing of these two phases is negative below the LCST and positive above, and the entropy change ΔS = – (dΔG/dT ...
As a result, the entropy decreases in the system, ΔS p < 0 for nearly all polymerization processes. Since depolymerization is almost always entropically favored, the ΔH p must then be sufficiently negative to compensate for the unfavorable entropic term. Only then will polymerization be thermodynamically favored by the resulting negative ΔG p.
Although entropy does increase in the model of an expanding universe, the maximum possible entropy rises much more rapidly, moving the universe further from the heat death with time, not closer. [ 96 ] [ 97 ] [ 98 ] This results in an "entropy gap" pushing the system further away from the posited heat death equilibrium. [ 99 ]
[1] [2] This means that aside to the regular mixing entropy there is another entropic contribution from the interaction between solvent and monomer. This contribution is sometimes very important in order to make quantitative predictions of thermodynamic properties. More advanced solution theories exist, such as the Flory–Krigbaum theory.
This process is associated with an increase in entropy. For most polymers, thermal depolymerization is chaotic process, giving a mixture of volatile compounds. Materials may be depolymerized in this way during waste management, with the volatile components produced being burnt as a form of synthetic fuel in a waste-to-energy process.
This local increase in order is, however, only possible at the expense of an entropy increase in the surroundings; here more disorder must be created. [ 9 ] [ 15 ] The conditioner of this statement suffices that living systems are open systems in which both heat , mass , and or work may transfer into or out of the system.
Here S is the entropy of the system; T k is the temperature at which the heat enters the system at heat flow rate ˙; ˙ = ˙ = ˙ represents the entropy flow into the system at position k, due to matter flowing into the system (˙, ˙ are the molar flow rate and mass flow rate and S mk and s k are the molar entropy (i.e. entropy per unit ...