Polymers confined to thin slabs

Lax et a/. (1981) have applied scaling law theory to a free polymer behaving as a self-avoiding walk in a thin slab of thickness h. This limits the span of the polymer chains leading to distortions in the direction parallel to the slab plane. The rms end-to-end distance of a self avoiding walk of isolated chains is given by 

Thermodynamically Limited Steric Stabilization The Phenomenology of Incipient Flocculation 

Two strategies have been exploited to study experimentally the stability of sterically stabhized dispersions  

The first strategy, studies of incipient instability, provides insights into the thermodynamic factors that control stability. Further, they show how optimum stability can be imparted and allow the bounds of stabilization (e.g. the upper and lower limits to temperature stability) to be determined. Necessarily, however, incipient instability studies examine dispersions in what might be described as their death throes. This could well change the very properties that we wish to study in order to understand how stability is imparted. It is therefore important to complement incipient instability studies with measurements on robustly stable dispersions. In this and the two subsequent chapters, the phenomenology of incipient flocculation will be discussed. The presentation of the properties of robustly stable dispersions will be deferred until Chapter 13. 

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