Some remarks concerning the swelling ability of three-dimensional polymers

SOME REMARKS CONCERNING THE SWELLING ABILITY OF THREE-DIMENSIONAL POLYMERS 

It logically follows from the above general notion that a network is defective if its swelling difiers from the theoretical predictions. Three types of network topological defects are generally under consideration  

Undoubtedly, all these types of defects are more or less peculiar to any real network polymer. However, one may question to what extent can the discrepancy between the theoretical predictions of swelling and the behavior of a real network be explained by these defects An even more important question is how correct is the current theory and whether it adequately assigns priorities to the most important factors that determine the swelling ability of polymer networks. 

In practice, the experimentally derived M values only occasionally coincide with the theoretical expectations. Fig. 7.20 illustrates a typical example of discrepancy between the values of AI and M for styrene— DVB copolymers [169]. For the networks with small amounts of DVB crosslinks Ml usuaUy exceeds M, and a large number of intramolecular 

Summarizing our experience with hypercrosslinked polystyrene networks, as well as with conventional gel-type and macroporous copolymers, we beheve that the topology of the network was undeservedly neglected by all theoretical treatments. By this we particularly mean that a network must be considered as an ensemble of interconnected and interpenetrating meshes or cycles, rather than as a combination of chains and junctions. 

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