Attempts to use coarse-grained molecular theories to calculate corrections to the random-phase approximation (RPA) for correlations in polymer mixtures have been plagued by an unwanted sensitivity to the value of an arbitrary cutoff length, i.e., by an ultraviolet (UV) divergence. We analyze the UV divergence of the inverse structure factor S(-1)(k) predicted by a "one-loop" approximation simil...

This modified (two-sided) Mullins-Sekerka model is a nonlocal evolution model for closed hypersurfaces, which appears as a singular limit of a modified Cahn-Hilliard equation describing microphase separation of diblock copolymer. Under this evolution the propagating interfaces maintain the enclosed volumes of the two phases. We will show by means of an example that this model does not preserve ...

Thin polymer films have attracted attention because of both their broad range of applications and of the fundamental questions they raise regarding the dynamic response of confined polymers. These films are unstable if the temperature is above their glass transition temperature Tg. Here, we describe freestanding thin films of centimetric dimensions made of a comb copolymer melt far from its gla...

This paper applies self-consistent field theory (SCFT) to discrete polymer chains consisting of a finite number of beads, N, joined together by freely jointed bonds of arbitrary potential, b(R). The numerics of this SCFT can be performed efficiently using spectral or pseudospectral algorithms, permitting its application to complex morphologies. To demonstrate its effectiveness, we examine diblo...

This paper explores the evolution of a sharp interface model for phase separation of copolymers in the limit of low volume fraction. Particles both exchange material as in usual Ostwald ripening, and migrate because of an effectively repulsive nonlocal energetic term. Coarsening via mass diffusion only occurs while particle radii are small, and they eventually approach a finite equilibrium size...

Holtz, F., Behrens, H., Dingwell, D.B. and Taylor, R.P., 1992. Water solubility in aluminosilicate melts of haplogranite composition at 2 kbar. In: Y. Bottinga, D.B. Dingwell and P. Richet (Guest-Editors), Silicate Melts. Chem. Geol., 96: 289-302. The compositional dependence of H20 solubility was investigated at 2 kbar and 800 °C in haplogranite melts (system SiO2-NaAISi3Os-KA1Si308 or Qz-Ab-O...

~ Thin liquid films of ordered dihlock copolymers deposited on a solid substrate form a multilayer stacking parallel to the solid surface. A multilayer with a finite extend can he stable, metastable, or unstable, depending on thc relative values of the surface ener&ics of the various interfaces. The spreading parameter and chemical potential of a n-layer are derived, and used for classifying al...

We present a simulation study of the equilibrium thermodynamic behavior of semiflexible diblock copolymer melts. Using discretized wormlike chains and field-theoretic Monte Carlo, we find that concentration fluctuations play a critical role in controlling phase transitions of semiflexible diblock copolymers. Polymer flexibility and aspect ratio control the order− disorder transition Flory−Huggi...