Network Olympic

This trapping technique can also be used to form networks with no cross-links. Mixing the same types of linear chain with large amounts of the cyclics and then functionally end-linking them could give sufficient cyclic interlinking to yield an Olympic or chain-mail network [3, 193, 200, 203], as is illustrated in Figure 5 [193], Attempts have been made to prepare and characterize such materials, because they could well have unusual elastomeric properties [204],... 

Figure 5. Preparation of a chain mail or Olympic network consisting entirely of interlooped cyclic molecules, without any cross-links [193]. Linear chains passing through the cyclics are difunctionally end-linked at the regions shown by the rectangles. The result is a series of interpenetrating cyclics, which would function as an elastomeric network.

In this section the unprecedented oligocatenanes, i.e. the [5]- and [7]catenanes 30 and 31 and the scarce experimental approaches to high molecular-weight linear polycatenane 9 have been presented. No synthetic Olympic network 32 has been reported to date, although their DNA analogs are known. The next section is dedicated to a new type of macromolecular architecture, structurally related to polycatenane 9, i.e. poly[2]catenanes. 

Figure 4.13 Preparation of a chain mail or Olympic network consisting entirely of inter-looped cyclics.294 Reproduced by permission of Butterworth.

It may also be possible to use the trapping technique to prepare networks having no cross links whatsoever. Mixed linear chains, with large amounts of cyclics, are difunctionally end linked to yield an Olympic or chain-mail network (figure 7.30). Such materials are similar in some respects to the catenanes and rotaxanes that have long been of interest to a variety of scientists and mathematicians. " Computer simulations could establish the conditions most likely to produce these novel structures. 

Preparation of a chain-mail or Olympic network, which has no cross links at all. Linear chains (light lines) passing through the cyclics (heavy lines) in part a are di-functionally end linked to form a series of interpenetrating cyclics in part b. 

It may also be possible to use this technique to form a network having no crosslinks whatsoever. Mixing linear chains with large amounts of cyclics and then t/tfunctionally end linking them could give sufficient cyclic interlooping to yield a chain-mail or Olympic network as depicted in Fig. 1.23 [96]. Such materials could have very unusual stress-strain isotherms [97]. 

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