“jacketing” effect, and even polymer 3 in Chart 1 is liquid crystalline when the
length of the alkoxy tails is appropriate.
The sizes of the LC structures formed by MJLCPs are closely correlated with the
side chains. For a rodlike MJLCP, the diameter of the supramolecular rod is
determined by the size of the side chain, while the length increases linearly with
increasing degree of polymerization (DP) which can be controlled when controlled/
living polymerization methods are used. Such a rodlike chain with tunable dimensions can serve as an excellent building block in constructing novel LC block
copolymers.
LC Phases of MJLCPs
As supramolecular mesogens, rodlike MJLCPs can form various columnar phases
with the parallel alignment of the polymer chains. On the other hand, sheetlike
MJLCPs containing side chains with more rigidity or special interactions can selforganize into smectic phases, and the polymer main chains are embedded in the
smectic layers and possess a parallel alignment.
Columnar Phases of MJLCPs
Nematic phases of the first MJLCPs (polymers 1 and 2 in Chart 1) synthesized were
initially proposed on the basis of polarized light microscopy (PLM) results (Zhou
et al. 1987, 1989). In fact, such nematic phases are columnar nematic (Col n ) phases
developed by the rodlike MJLCP supramolecular mesogen, with the consideration of
the jacketed model. Many other MJLCPs also exhibit Col n phases (Jin et al. 2010;
Fig. 2 Schematic representation of different LC phases formed by MJLCPs. (Reprinted and
adapted with permission of the Royal Society of Chemistry Chen et al. 2010)
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Z. Shen