Le Journal de Physique Colloques

Journal Information
ISSN: 04491947
Published by: EDP Sciences
Total articles ≅ 15,207

Latest articles in this journal

E. L. Thomas, J. R. Reffner, J. Bellare
Published: 1 December 1990
Le Journal de Physique Colloques, Volume 51; https://doi.org/10.1051/jphyscol:1990736

Diblock copolymer macromolecules may be viewed as giant amphiphiles. Such molecules readily self-assemble into a wide variety of structures which exhibit intermaterial dividing surfaces of approximately constant mean curvature. Order-disorder transitions in bulk materials result in ordered microdomain structures of BCC spheres, hexagonally packed cylinders and stacked lamella. An additional structure, the ordered bicontinuous double-diamond (OBDD) is also shown to occur as a cubic phase between the cylindrical and lamellar morphologies. The interface structure of the OBDD resembles a recently discovered family of constant mean curvature surfaces which include the Schwarz D minimal surface. Another interface structure which approximates Scherk's First Surface is a 90 twist boundary between grains of lamella. Blending of diblock copolymer with homopolymer provides a versatile binary system which displays a critical micelle concentration, spherical and cylindrical micelles, lamellar vesicles as well as ordering transitions depending on composition. The penetration of homopolymer into one side of the near-interface region accounts for the observed variations in interface curvature in blends from that of the pure diblock. Confining geometries, such as external surfaces, thin films and microdroplets can influence interface structures. Chaotic bicontinuous as well as parallel surface structures such as concentric spherical shells are shown to occur in microdroplets of a diblock copolymer which forms lamellar microdomains in the bulk
Published: 1 December 1990
Le Journal de Physique Colloques, Volume 51; https://doi.org/10.1051/jphyscol:1990721

The global spatial requirement set by the composition of a binary surfactant-water system can be expressed as a function of the local intrinsic geometry of the surfactant film, assuming a reasonably homogeneous film, which is equivalent to a film of low bending energy. These relations are calculated for (quasi-)homogeneous hyperbolic, elliptic (spheres) and parabolic (cylinders) geometries. It is suggested that the crystallinity of some surfactant mesophases is a result of the homogeneity constraint. Detailed theory of structures found in bicontinuous cubic phases, as well as experimental techniques for deciphering the microstructure of these phases is presented
S. Lidin
Published: 1 December 1990
Le Journal de Physique Colloques, Volume 51; https://doi.org/10.1051/jphyscol:1990723

Supplément au Journal de Physique Colloques, Journal de Physique Archives représente une mine dinformations facile à consulter sur la manière dont la physique a été publiée depuis 1872.
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