ISSN:
0887-6266
Keywords:
block copolymers
;
microstructures
;
conformational asymmetry
;
complex phases
;
self-consistent field theory
;
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The standard parameters controlling AB diblock copolymer phase behavior are χN and fA, where χ is an A-B segment interaction parameter, N is the overall degree of polymerization, and fA is the volume fraction of the A block. Recently, it has been recognized that the ratio of the A and B statistical segment lengths αA/αB also represents another important parameter. Here, we theoretically examine the effects of this latter parameter on the phase behavior using the standard Gaussian chain model. Calculations are performed using both self-consistent field theory (SCFT) and strong segregation theory (SST). The ratio αA/αB is shown to have strong effects on order-order phase boundaries. Furthermore, it significantly affects the relative stability of the complex phases. In particular, it enhances the metastability of the perforated lamellar phase and may actually cause it to become an equilibrium structure. We also illustrate that varying αA/αB produces large changes in the relative domain spacings at order-order phase boundaries, which could strongly affect the kinetics of these transitions. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35: 945-952, 1997
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
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