Spinodal-assisted crystallization in polymer melts
  Recent experiments in some polymer melts quenched below the melting temperature have reported spinodal kinetics in small-angle X ray scattering before the emergence of crystalline structure. To explain these observations we propose that the coupling between density and chain conformation induces a liquid-liquid binodal within the equilibrium liquid--crystalline solid coexistence region. A simple phenomenological theory is developed to illustrate this idea, and several experimentally testable consequences are discussed. Shear is shown to enhance the kinetic role of the hidden binodal. 
Peter D. Olmsted, Wilson C. K. Poon, T. C. B. McLeish, N. J. Terrill,   and A. J. Ryan