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ZB 10 - Soft Condensed Matter (R. Holyst)

We are different, but we all do great Science; and we have a lot of fun doing it!
We are different, but we all do great Science; and we have a lot of fun doing it!
We are different, but we all do great Science; and we have a lot of fun doing it!
We are different, but we all do great Science; and we have a lot of fun doing it!
We are different, but we all do great Science; and we have a lot of fun doing it!
We are different, but we all do great Science; and we have a lot of fun doing it!
We are different, but we all do great Science; and we have a lot of fun doing it!
We are different, but we all do great Science; and we have a lot of fun doing it!

Publication

The structure and phase transitions in polymer blends, diblock copolymers and liquid crystalline polymers: The Landau-Ginzburg approach

Author(s): Holyst, R and Vilgis, TA
Title: The structure and phase transitions in polymer blends, diblock copolymers and liquid crystalline polymers: The Landau-Ginzburg approach
Abstract: The polymer systems are discussed in the framework of the model. The model is derived from the mesoscopic Edwards via the conditional partition function. We discuss flexible, and rigid polymers. The following systems are studied: blends, flexible diblock and multi-block copolymer melts, random melts, ring polymers, rigid-flexible diblock copolymer melts, of copolymers and homopolymers and mixtures of liquid polymers. Three methods are used to study the systems: model, self consistent one-loop approximation and self field theory. The following problems are studied and the phase diagrams, scattering intensities and correlation single chain statistics and behavior of single chains close critical points, fluctuations induced shift of phase boundaries. In we shall discuss shrinking of the polymer chains close to the point in polymer blends, size of the Ginzburg region in polymer and shift of the critical temperature. In the rigid-flexible copolymers we shall discuss the density nematic order parameter function. The correlation functions in this system are found oscillate with the characteristic period equal to the length of the part of the diblock copolymer. The density and nematic order measured along the given direction are anticorrelated. In the diblock copolymer system we shall discuss various phases the double diamond and gyroid structures. The single chain in the disordered phase of a flexible diblock copolymer is shown to deviate from the Gaussian statistics due to In the one loop approximation one shows that the diblock chain is stretched in the point where two incompatible blocks but also that each block shrinks close to the microphase separation The stretching outweighs shrinking and the net result is the of the radius of gyration above the Gaussian value. Certain of homopolymer/copolymer systems are discussed. Diblock solubilize two incompatible homopolymers by forming a interface between them. The interface has a positive saddle modulus which means that the interfaces in the disordered phase be characterized by a negative Gaussian curvature. We also show in such a mixture the Lifshitz tricritical point is encountered. properties of this unusual point are presented. The Lifshitz, and disorder lines are shown to provide a useful tool for local ordering in polymer mixtures. In the liquid crystalline the isotropic nematic phase transition is discussed. We concentrate on static, equilibrium properties of the polymer systems.
Pages: 573-643
Journal: MACROMOLECULAR THEORY AND SIMULATIONS
Volume: 5
ID: ISI:A1996VA04200001
Year: 1996
DOI: 10.1002/mats.1996.040050401