Abstract:
:The configurations of the hydrocarbon chains in micelles are severely constrained by the space-filling requirements of the chain segments, by the continuity of the chains, and by the micellar geometry. A statistical theory that takes full account of these constraints is developed by using a lattice model. The chain ends are deduced to be nonuniformly distributed, with maximal incidence approximately midway between the center of the micelle and the outer surface. Whereas the chain disorder near the outside of the hydrophobic core may approach that of a liquid, crowding of the chains near the core center imposes a degree of order approaching that in a crystal. These results are at variance with the prevailing view that the micellar interior resembles a "liquid hydrocarbon droplet." Also discussed are the effects of curvature on the chain configurations in monolayers and bilayers. It is found, for example, that the "disorder gradients" in inner and outer half-bilayers of small vesicles should be substantially different. Implications of these results are discussed.
journal_name
Proc Natl Acad Sci U S Aauthors
Dill KA,Flory PJdoi
10.1073/pnas.78.2.676subject
Has Abstractpub_date
1981-02-01 00:00:00pages
676-80issue
2eissn
0027-8424issn
1091-6490journal_volume
78pub_type
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