Second-order phase transition phenomenon

Transition from normal conductivity to superconductivity is a virtual perfect second-order phase transition that is, there is no latent heat or a sharp finite discontinuity in the specific heat therefore, it is a cooperative phenomenon. 

Glass transition Change of state of an amorphous or semi-crystalline polymer from a rubbery (or viscous) state to a glassy state. The glass transition is not a thermodynamic first- or second-order phase transition. It is a relaxation phenomenon which is characterized by a general enhancement of molecular motion in the polymer at the glass transition temperature. 

In second-order or nearly second-order phase transitions, the dielectric dispersion is observed to show a critical slowing-down a phenomenon in which the response of the polarization to a change of the electric field becomes slower as the temperature approaches the Curie point. Critical slowing-down has been observed in the GHz region in several order-disorder ferroelectrics (e.g. Figs. 4.5-8 and 4.5-9) and displacive ferroelectrics (e.g. Fig. 4.5-10). The dielectric constants at the Curie point in the GHz region are very small in order-disorder... 

Its N value is 1.4 (measured with l p=2.5, 5 and 10 C/min). The second peak at 135 C is the nematic-isotropic transition peak. Its N value is 1.3 (same heating rates). These two N values are typically the ones of first order phase transitions. The heat capacity of PAA is small compared to the height of the peak. Even if an anomalous second order phenomenon occurs, increasing the heat capacity jump under the nematic-isotropic peak by 100% or 200%, it cannot shift N towards two in a detectable way. 

In a series of papers Hachisu. Kobayasi, and Kose (375-379) reviewed the literature and investigated the subject in further detail. The particles can form ordered arrays without being in actual contact. In these arrays particles are all the same size and other sizes are excluded. The phenomenon involves a phase transition when the concentration exceeds a certain volume fraction, usually 0.5 . 0.1, whereby a second more concentrated phase is formed within which the particles are in an ordered arrangment. This is known as the Kirkwood-Alder transition (380-382) and is a purely statistical effect that does not require an attractive potential for its explanation. It is inhibited when ionic repulsion forces exceed a low level. The transition can occur in suspensions in aqueous and nonaqueous liquids. In aqueous systems it will not occur even when the particles are very uniform, unless the system is low in electrolytes. 

The glass transition generally occurs over a relatively narrow temperature span and is similar to the solidification of a liquid to a glassy state it is not a phased transition. Not only do hardness and brittleness undergo rapid changes in this temperature region, but other properties, such as the coefficient of thermal expansion and specific heat, also change rapidly. This phenomenon has been called second-order transition, rubber transition, and rubbery transition. The word transformation has also been used instead of... 

---