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Computer Simulations of Wormlike Micelles
| Content Provider | Scilit |
|---|---|
| Author | Padding, Johan T. Otter, Wouter K. Den Briels, Wim J. |
| Copyright Year | 2007 |
| Description | Amphiphilic molecules may self-assemble in a great variety of morphological structures. A convenient parameter, which quantifies the importance of the molecular structure, is the packing parameter p = $v_{s}$ /(al), where $v_{s}$ is the volume of the hydrophobic tail of the amphiphile, a is the area occupied by its hydrophilic head group, and l the length of its tail. In dilute solutions micellar structures tend to be spherical for values of the packing parameter around 1/3 and rodlike when p is close to $1/2.^{ 1 }$ With increasing surfactant concentration, rodlike micelles grow into long cylindrical structures or worms, whose lengths finally by far exceed their persistence lengths. The persistence length $l_{p}$ is the length over which the worm may be considered to be a stiff rod. It is related to the bending rigidity coefficient κ by $l_{p}$ = $κ/(k_{B}$T), with $k_{B}$ Boltzmann's constant and T the temperature. Already at relatively small concentration, wormlike micelles enter the 82semidilute regime and form an entangled network, very much like the entangled network occurring in a polymer solution. Such a network enhances the viscosity of the solution, sometimes by several orders of magnitude, and introduces elastic properties. Unlike polymers, however, the wormlike micelles can reversibly break, and the break-up rate is sensitive to temperature, flow or stress conditions, concentrations of various components, and other parameters (see Chapter 4, Sections 4.2.5 and 4.4; Chapter 8, Sections 8.2.2 and 8.4.2; and Chapter 10). As a result, wormlike micelles have a rich rheology, rendering them perfect functional fluids in many industrial $applications.^{ 2 }$ Book Name: Giant Micelles |
| Related Links | https://content.taylorfrancis.com/books/download?dac=C2009-0-10072-3&isbn=9780429124969&doi=10.1201/9781420007121-3&format=pdf |
| DOI | 10.1201/9781420007121-3 |
| Language | English |
| Publisher | Informa UK Limited |
| Publisher Date | 2007-05-30 |
| Access Restriction | Open |
| Subject Keyword | Book Name: Giant Micelles Polymer Science Elastic Properties Micelles Amphiphilic Hydrophobic Structures Packing Entangled Wormlike |
| Content Type | Text |
| Resource Type | Chapter |
