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Fluid lamella equilibrium

In general, any transformation of the thermodynamic state of the confined lamella is associated with a variation of a characteristic function assuming a global minimum if the lamella is in thermodynamic equilibrium. However, there arc various ways in which such a transformation may be effected in practice. Hence, the precise form of the characteristic function may vary between different (experimental) situations. Below we shall briefly discuss the characteristic functions that are key to the analysis of confined fluids. [Pg.22]

Some transitions that are only known for macromolecules, however, will not be mentioned at all since they are covered elsewhere in this Encyclopedia (see, eg. Gel Point). Also we shall not be concerned here with the transformations from the molten state to the solid state of polymeric materials, since this is the subject of separate treatments (see Crystallization Kinetics Glass Transition Viscoelasticity). Unlike other materials, polymers in the solid state rarely reach full thermal equilibrium. Of course, all amorphous materials can be considered as frozen fluids (see Glass Transition) Rather perfect crystals exist for metals, oxides, semiconductors etc, whereas polymers typically are semicrystalline, where amorphous regions alternate with crystalline lamellae, and the detailed structure and properties are history-dependent (see Semicrystalline Polymers). Such out-of-equilibrium aspects are out of the scope of the present article, which rather emphasizes general facts of the statistical thermodynamics (qv) of phase transitions and their applications to polymers in fluid phases. [Pg.5482]


See other pages where Fluid lamella equilibrium is mentioned: [Pg.11]    [Pg.752]    [Pg.20]    [Pg.569]    [Pg.82]    [Pg.20]    [Pg.22]    [Pg.155]   
See also in sourсe #XX -- [ Pg.17 ]

See also in sourсe #XX -- [ Pg.17 ]




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Fluid lamella

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