Accelerated Crystal Nucleation in the Concentrated Phase

Let us switch our perspective to the other side, and see how the prior phase separation affects polymer crystal nucleation. We know that polymer crystallization normally needs a relatively large degree of supercooling. If liquid-liquid phase separation happens before a polymer solution has reached a sufficient degree of supercooling, the practical concentration for polymer crystallization will be changed. 

As demonstrated in Fig. 11.4, we designed three sets of energy parameters for the solutions of polymers each containing 128 monomers in the cubic lattice space 64. They display the same equilibrium melting points near the concentration 0.125 in the semi-dilute solution region, but clearly different critical points for phase separation. 

If the homogeneous C2 and C3 solutions with the concentration of 0.125 are quenched to a low temperature of l.5EJk for isothermal crystallization, their structure factors as a function of time are shown in Fig. 11.5a, b. According to the introduction in the Sect. 9.2, Fig. 11.5a shows the typical evolution of structure 

11 Interplay Between Phase Separation and Polymer Crystallization 

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