Monomolecular micelles

Newkome GR, Moorefield CN, Baker GR, Saunders MJ, Grossman SH. Chemistry of micelles. 13. Monomolecular micelles. Angew Chem 1991 103 1207-1209. 

In another study, Selb and Gallot investigated the conformational properties of poly(styrene-g-4-vinyl-N-ethylpyridinium bromide) in water/methanol/LiBr mixtures [306]. The graft copolymers did not show intermolecular association in contrast to the linear block copolymers. Viscometric results showed that these graft copolymers also form compact, star-like monomolecular micelles with polystyrene cores and poly(4-vinyl-V-ethylpyridinium bromide) coronas, which resemble the polymolecular micelles of diblock materials. 

In water, PEO-PPO-PEO shows two breaks in the slopes of surface tension versus surfactant concentration plots compared to one in more common pure surfactants (Figure 4.1). The break at lower conemtration has been accepted by Alexandiidis et al. (1994) as CMC, and has been described by Yu et al. (1992) as the point of monomolecular micelle formation. The break point at higher concentration beyond which the surface traision does not change has been accepted as the CMC by Yu et al. (1992), who describe it as the point of... 

Experimentally it has proved extremly difficult to investigate the possibility of a collapsed coil effect in single block copolymer chains i.e. the formation of so-called monomolecular micelles.). This is undoubtedly because the phenomenon is always likely to occur very near or under conditions where conventional micelle formation occurs. As pointed out by Cowie, who has reviewed the experimental evidence available, many of the dilute solution studies are open to some flexibility of interpretation and a new approach to the experimental problem is required. 

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