Copolymer systems mesoscopic morphology

Application DPD Simulation in Multiscale. DPD simulation method in multiscale i.e. parameter derived from atomistic simulations has been successfully implemented for different real polymeric systems. The mesoscopic morphology of linear and graft- fluorinated block copolymers has been investigated by Ozan et al. Polyethylene and poly (L-lactide) polymer blends and di-block copolymers have been investigated as a function of chain... 

In what follows we will discuss systems with internal surfaces, ordered surfaces, topological transformations, and dynamical scaling. In Section II we shall show specific examples of mesoscopic systems with special attention devoted to the surfaces in the system—that is, periodic surfaces in surfactant systems, periodic surfaces in diblock copolymers, bicontinuous disordered interfaces in spinodally decomposing blends, ordered charge density wave patterns in electron liquids, and dissipative structures in reaction-diffusion systems. In Section III we will present the detailed theory of morphological measures the Euler characteristic, the Gaussian and mean curvatures, and so on. In fact, Sections II and III can be read independently because Section II shows specific models while Section III is devoted to the numerical and analytical computations of the surface characteristics. In a sense, Section III is robust that is, the methods presented in Section III apply to a variety of systems, not only the systems shown as examples in Section II. Brief conclusions are presented in Section IV. 

Such ABC-triblock systems offer the opportunity of creating ordered morphologies containing simultaneously mesoscopic structures of different dimensionality, some selected examples are depicted in Figure 10. Yet, scope and limitations in the morphologies of ternary block copolymers are not fully explored [107-109,110] and theoretical approaches for their quantitative understanding are still at the beginning [111]. 

The case of block copolymers is peculiar and deserves a specific development. In such a structure, the A and B blocks are connected to one another by a covalent bond, and their respective molar mass and composition can be varied independently. Being incompatible, A and B blocks tend to minimize their surface of contact but, contrary to the mere blends of two polymers they cannot phase separate to a macroscopic scale due to the bond which links them. Classical composition-temperature phase diagrams cannot be constructed for block copolymers as for the corresponding blends. Indeed the A and B blocks are forced to self-organize in domains of more reduced nano- or mesoscopic size. The transition from a homogeneous blend to a system composed of ordered phases as well as the size and the morphology of these ordered phases depend on two elements the product Xab " (X = total degree of polymerization) and the dissymmetry in size of the two blocks. 

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