Critical dynamics, strongly-interacting behavior

While this helps us to describe the conformation of the unperturbed molecule in a melt, the rheological behavior of a melt is dramatically different from that of a dilute solution if the molecular weight exceeds a certain critical value. This is the result of an extremely important phenomenon that occurs in a melt and has no counterpart in the dilute solution. Over a certain rather narrow range of molecular weights the dynamic interaction between polymer molecules starts to have a very marked effect on the dynamic behavior of the melt. This strong interaction is traditionally said to be due to entanglements, although it is now understood that... 

Critical behavior of, and electrical conductivity percolation in, microemulsions is much dependent on the dynamics of stick/ collisions between droplets of oil (water) present in oil-in-water (water-in-oil) microemulsions (see Chapter 5). Sticky collisions refer to collisions that bring assembly cores into contact. During the time of contact matter may be transferred from one assembly to another. Such collisions occur in systems with strong attractive interactions between assemblies. 

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