Entanglements, catenane-like

There are few examples of ID networks interpenetrating, perhaps due to the requirement of ring motifs of suitable size to be present so that the catenane-like interactions needed can be formed. Nonetheless, ID networks can interpenetrate in different ways, leading to entanglements... 

Entangled systems are extended arrays, more complex than their constituents, that are comprised of individual motifs forming, via interlocking or interweaving, periodic architectures infinite in at least one dimension. Simple interdigitation is not considered here. As previously stated, most of the entangled arrays can be considered regularly repeated infinite versions of finite molecular motifs like catenanes, rotaxanes and pseudo-rotaxanes. 

Interpenetrating networks have an obvious relationship to molecular catenanes indeed, they can be thought of simply as catenated polymers. Similarly, entangled networks with rotaxane-like relationships have also been reported. ... 

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