We study theoretically the effect of adding polymer to the dilute lamellar phase of surfactant solutions. The polymer, assumed semidilute and in a good solvent, is taken to have a repulsive or attractive interaction with surfactant bilayers, but has no other effect on their properties. Such polymers can mediate an attractive or repulsive interaction between bilayers which we combine with pre-ex...

As a type of novel semi-crystalline block copolymers, the final properties of olefin block copolymers (OBCs) greatly depend on the crystalline and phase-separated structures. In the present work, we systematically investigated the influence of self-nucleation and annealing on the lamellar and mesophase-separated structure of OBCs. According to the crystalline and melting behavior after self-nuc...

Introduction In the past 15 years, much attention has been paid to the effects of shear flow on the structure of the lyotropic phase of surfactant systems, especially on the lamellar phase. Among them, the most striking result may be the transition from the lamellar phase to the "onion phase" where all the space is filled by multilamellar vesicles alone [1]. Although this type of transition has...

In this work, a novel cube-shaped cationic lipid based on the imidazolium salt of polyhedral oligomeric silsesquioxane (POSS) was complexed with double-stranded DNA. Because of the negative spontaneous curvature of the cationic POSS imidazolium lipid, an inverted hexagonal phase resulted above the melting point of POSS crystals. Depending on the competition between the crystallization of POSS m...

Different types of lamellar-within-lamellar structure formations in A-b-(B-b-A)(n)-b-C terpolymer melts, with a volume fraction of components A, B, and C in the ratio of 1:1:2, are analyzed in the strong segregation limit using a simple theoretical approach. We consider the lamellar, parallel lamellar-within-lamellar, and perpendicular lamellar-within-lamellar self-assembled states. The influen...

Lattice Boltzmann simulations are used to investigate spinodal decomposition in a two-dimensional binary fluid with equilibrium lamellar and droplet phases. We emphasise the importance of hydrodynamic flow to the phase separation kinetics. For mixtures slightly asymmetric in composition the fluid phase separates into bulk and lamellar phases with the lamellae forming distinctive spiral structur...

We consider a spin model for applications to oil-water —amphiphilic-surfactant mixtures near the region where those phases coexist. We analyze this model assuming that oil and water molecules cannot be treated symmetrically, given that they do exhibit different chemical potentials. Using a mean-field approximation, we find that the modulated phase assumes two possible arrangements, such as shee...

We develop a phase-field model of eutectic growth that uses three phase fields, admits strictly binary interfaces as stable solutions, and has a smooth free energy functional. We use this model to simulate oscillatory limit cycles in two-dimensional lamellar growth, and find a continuous evolution from lowamplitude oscillations to successive invasions of one solid phase by the other when the la...