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[摘要]：The phase separation of polymer blend films on the stripe patterned surface is numerically investigated by coupling the Flory-Huggins-de Gennes equation with the Cahn-Hilliard-Cook equation. The kinetic pathway and its mechanisms are analyzed in both real space and reciprocal space. Compared to experimental measurements, the simulated results exhibit more complete kinetic pathways of pattern-directed phase separation. It is found that the extreme fluctuation of the chemical potential at the edges of stripes leads to the formation of the branch structure. Our simulated results indicate that the phase inversion, occurring not only in the polymer/air interface but also in the bulk, can extensively affect the relations between the isotropic phase separation and the periodic structure. The analysis in reciprocal space shows that the evolution of the phase morphologies in the polymer/air interface obeys a (1)/(3) power law for a thick film, consistent with the experimental results. It is also found that the amplitude change of the first diffraction peak can reflect the kinetic pathway of the phase structure in the polymer/air interface very well. A narrower strip periodicity corresponds to an earlier phase inversion and an earlier appearance of the droplet arrays in strips. |
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