Non-uniformities in polymer/liquid crystal mixtures II. Nematic nucleation

• Published in: The European physical journal. E, Soft matter and biological physics Soft matter and biological physics, 2002-09, Vol.9 (1), p.89-95
• Main Authors: Matsuyama, A, Evans, R M L, Cates, M E
• Format: Article
• Language: English
• ISSN: 1292-8941
• DOI: 10.1140/epje/i2002-10062-8

We theoretically model the nucleation of nematic droplets during phase ordering in mixtures of a flexible polymer and a low-molecular-weight liquid crystal. By appealing to classical nucleation theory (CNT), we calculate the energy barrier to nucleation and the size of a critical nucleus. We study the influence of a metastable intermediate phase on the nucleation of the nematic. Below a triple point in the phase diagram, there are two distinct mechanisms for the formation of a nematic nucleus: 1) direct nucleation from the isotropic phase and 2) nucleation via a precursor metastable isotropic phase. We calculate the crossover concentration as a function of temperature, delineating the regions of the phase diagram in which each mechanism prevails. In the latter case, the presence of a hidden metastable isotropic-isotropic binodal may either promote or delay the nucleation of a nematic phase.