Interpenetration without compression

Figure 7.13 Two limiting modeis for steric stabilization with amphiphilic macro-molecular surfactants, (a) Interpenetration of adsorbed layers without compression (b) compression without interpenetration.

Interpenetration without Compression without compression interpenetration... 

Interpenetration without Compression without f S- 3.2A Schematic representation of the compression interpenetration interaction of two polymer layers. 

Since crystals are not indefinitely compressible there is evidently a repulsion force which operates when the electron clouds of the ions begin to interpenetrate (without electron-sharing between the ions). This repulsion energy is not readily calculable, and Born represented it by 5/r , a function which increases very rapidly with decreasing distance r if n is large, that is, it corresponds to the ions being hard spheres. The expression for the lattice energy is now... 

Concentration effects in solutions of randomly branched polymers are similar to those in solutions of other types of branched macromolecules but exhibit some specific features. Similar to the case of star-branched polymers, in semidilute solutions of fairly monodisperse branched polymers beyond the overlap concentration cj ja,jched- / branched, individual macromolecules contract without significant interpenetration. Appearance of a sharp corrdation peak in the stmrture fartor and vanishing osmotic compressibility in the concentration range dose to are the concomitant effects. 

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