Anisotropic metastable transitions

Above the critical concentration v the solution becomes metastable and separates into two phases — isotropic and anisotropic. The condition of thermodynamic equilibrium of the two phases corresponds to the equality of the chemical potentials of each of the components in each of the coexisting phases. The concentration corresponding to a complete transition to the anisotropic state, v, is 1.56 times as high as vf (see also... 

Because of the softness of interactions in block copolymers (here we restrict our consideration to flexible molten blocks above the glass transition temperature), thermal fluctuation in these systems is expected to be significant, especially near the order-disorder transition temperatures (Fredrickson and Helfand, 1987). In addition, the long relaxation times, due to the slowness of the motion of polymers, often lead to metastable and other kinetic states. Thus, full understanding of the self-assembly in block copolymers requires understanding of the nature of fluctuation, metastability, and kinetic pathways for various transitions. Most of this article is focused on theoretical studies of these issues in the simpler AB block copolymers. A key concept that emerges from these studies is the concept of anisotropic fluctuations first, these fluctuations determine the stability limit of an ordered phase second, they are responsible for the emergence of new structures... 

A. Water. Other systems of the substance water. B, Sulphur. Metastable systems. Bivariant systems. C. Tin. Transition point. D. Phosphorus, E. Liquid Crystals or Anisotropic Liquids. Nature of liquid cryst s. Equilibrium relations in the case of liquid crystals. 

Hu W, Cai T (2008) Regime transitions of polymer crystal growth rates molecular simulations and interpretation beyond Lauritzen-Hoffman model. Macromolecules 41(6) 2049-2061 Hu W, Frenkel D (2004) Effect of metastable liquid-liquid demixing on the morphology of nucleated polymer crystals. Macromolecules 37(12) 4336-4338 Hu W, Frenkel D (2005) Polymer crystallization driven by anisotropic interactions. Adv Polym Sci 191 1-35... 

Non-equilibrium states are often anisotropic and consist of preferentially oriented/aligned polymer chains. Thus, under appropriate processing conditions, these non-equilibrium states represent, or evolve into, ordered structures and metastable states, which exhibit properties not achievable under equilibrium condition. For example, changes at the conformational level of polymers may lead to macroscopic changes in behaviour, e.g. represented by changes in the glass transition temperature. 

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