Why non-covalent bonds

One of the foremost points of this review is the evident viability of using non-covalent bonds as integral elements in the assembly of PLC supramolecules. They not only modify existing mesomorphic behavior but, even more significantly, they can induce mesomorphic behavior. 

They thus provide an entirely new tool with which to tailor PLCs for specific ends. 

They are expected to possess unique properties due to the lability of the non-covalent bonds, and, from a synthetic viewpoint, many of the usual molecular parameters that control the PLC characteristics can be more easily accessible. The latter include the length and type of spacer and tail, the type of mesogen, the type of polymer backbone, and the molar mass and polydispersity of the polymer. Additional molecular parameters are introduced in conjunction with the choice of functional groups. Furthermore, a number of useful functional polymers are available either commercially or through straightforward synthetic methods. It is also a simple matter to obtain a variety of supramolecular copolymer PLCs and network PLCs, as well as, in principle, a variety of other architectures. A number of examples of these aspects have been given in this review. 

The use of small molecules as at least one of the functional constituents allows a tailorable combination of polymer and monomer properties. Moreover, any temperature dependence in the lability of the non-covalent bonds will also result in a temperature-dependent polymer-monomer character. Low viscosities at higher temperatures 

This review has presented what is a beginning in the development and understanding of supramolecular PLCs. Many questions about these materials, a number of which were posed above, must still be addressed. Their limits and their possibilities remain to be circumscribed. However, the richness of their potential is indisputable. 

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