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with increasing spacer length, indicating substantial conformational differ-
ences between segmented LCPs with an odd number of methylene spacer
units (lower transition temperatures) and their even-numbered counterparts.
Recently,wehaveintroducedtheuseofacyclicdienemetathesis(ADMET)
polymerization as an approach to the preparation of main-chain LCPs [13].
The preparation of side-chain LCPs is comparatively simpler [6] and in-
volves chain-growth polymerization of vinyl- or vinylidene-functionalized
mesogens. Alternatively, mesogens may be post-polymerization grafted (the
so-called polymer analogous synthesis) to polymers which contain appropri-
ate functional groups on the backbone [14, 15].
Recently, the use of specific non-covalent interactions has lead to the de-
velopment of a wide range of supramolecular polymers [16-19]. In this class
of interesting polymers small molecule and/or polymeric units are designed
to contain supramolecular motifs in order to self-assemble a desired poly-
meric aggregate. One major advantage of such a self-assembly process is the
ability to control the resulting supramolecular architecture of the polymer ag-
gregates by simply tailoring the structure of the starting units. Another aspect
that differentiates supramolecular polymers from more conventional covalent
bonded structures is their dynamic nature, which has potentially significant
consequences for the thermomechanical properties of such systems [20]. The
properties of such non-covalently bound aggregates have a strong depen-
dence not only on their core components but also on the nature (stability
and dynamics [21]) of the supramolecular interactions that control the self-
assembly process. The degree of the interaction between the starting units
depends, to a large extent, on the strength of the supramolecular interaction,
and the unit concentration, as well as a range of environmental conditions
(such as temperature, pH, solvent, etc).
The ability to combine supramolecular chemistry with liquid crystallinity is
very attractive for several reasons. It has been well known for a long time in the
liquid crystal community that non-covalent interactions have a great effect on
a material's liquid crystallinity. Therefore, it is expected that designing specific
non-covalent interactions into monomer units can result in a number of effects,
including inducing liquid crystallinity upon non-mesogenic starting materi-
als, changing the nature of the LC phase and/or changing the stability of the LC
phase. Furthermore, the combination of the dynamic behavior of the supramo-
lecular polymer along with the temperature sensitivity of the LC phase offers
exciting opportunities for (multi-step) stimuli-responsive materials. From the
point of view of supramolecular materials it has been proposed that the order
imposed by liquid crystallinity can been utilized to enhance the interaction be-
tween constituent molecules, thus allowing access to SLCPs with relatively weak
hydrogen bonding interactions between monomers [22-38].
Over the years there have been a number of excellent papers [39-41] that
cover different aspects of this burgeoning field. The field of supramolecular
materials and LCPs is a large one and includes the supramolecular ordering of
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