Huggins coefficient hard spheres

The above argument shows that complete overlap of coil domains is improbable for large n and hence gives plausibility to the excluded volume concept as applied to random coils. More importantly, however, it introduces the notion that coil interpenetration must be discussed in terms of probability. For hard spheres the probability of interpenetration is zero, but for random coils the boundaries of the domain are softer and the probability for interpenetration must be analyzed in more detail. One method for doing this will be discussed in the next section. Before turning to this, however, we note that the Flory-Huggins theory can also be used to yield a value for the second virial coefficient. 

Similar results, which showed behavior of the viscosity according to a hard-sphere model, have been observed for a variety of O/W microemulsion systems such as Brij 96-butanol-hexadecane-water [52], Tween 60-Span 80-glycerol-paraffin-water [53], and Brij 96-pentanol-hexadecane-water [54]. Again the extrapolated intrinsic viscosity is found to be about 60% greater than expected according to Einstein s equation and the Huggins coefficient kn [cf Eq. (13)] to be about 1.8 [52]. This shows that such behavior will quite generally be observed for droplet-type microemulsions irrespective of the inter-... 

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