The Twinkling Fractal Theory is a theory of the glass transition based on solid and liquid fractal clusters. A cluster is a group of segments or molecules which interact to have certain properties characteristic of the group or set. A liquid cluster has the properties of liquid in which the segments or molecules are free to move with respect to other segments of the group or set. The solid or percolation structure is one in which the segments of molecules of a set or group are not free to move but the whole set tends to move in a coordinated fashion, i.e. becoming rigid. Near the glass transition the solid and liquid clusters interchange in dynamic equilibrium with a vibrational density of states corresponding to a twinkling effect. The solid-to-liquid twinkling frequencies are controlled by the Boltzmann population of intermolecular oscillators in excited energy states of their anharmonic potential energy functions. The complex twinkling dynamics existing near Tg produces a continuous relaxation spectrum with many different length scales and times associated with the fractal clusters. This theory uses only one constant B, which appears to be the same of all polymers in contrast to the WLF theory which requires two constants which must be determined for every material. The Twinkling Fractal Theory describes the strong and fragile nature of the viscosity behavior of liquids and the rate and temperature dependence of the yield stress in polymers. Wool, Richard P. (R.P. Wool, 10/11/2009; accepted for publication in the Journal of Polymer Science Part B) 

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