Liquid Crystalline Assembly of Rod–Coil Molecules - Liquid Crystalline Functional Assemblies and Their Supramolecular Structures - page 94

Fig. 21 Perforated lamellar structure hierarchically formed by poly(styrene- b -(2,5-bis[4-
methoxyphenyl] oxycarbonyl)styrene) structure. Reprinted with permission from [107].
© 2005 American Chemical Society
By laterally linking aromatic mesogens directly to polymer backbones,
mesogen-jacketed liquid crystalline polymers as a rod-coil copolymer can
be achieved [104-106]. Zhou and coworkers reported on the supramolecular
structures of these type of rod-coil copolymers composed of poly(styrene-
b -(2,5-bis[4-methoxyphenyl] oxycarbonyl)styrene) [107]. The strong interac-
tion between the side-chain mesogens and polymer backbone induces forma-
tion of rigid columns of mesogens. The macromolecular columns possess ori-
entational order and then these rigid columns self-assemble into a columnar
nematic of hexagonal mesophase. On increasing the volume fraction of poly-
styrene blocks, the mesophases change from lamellar to perforated lamellar
structures, where the polystyrene perforates the macromolecular rigid col-
umn layer of poly(2,5-bis[4-methoxyphenyl]oxycarbonyl)styrene (Fig. 21).
5
Conclusions
A variety of different supramolecular structures can be formed by self-
assembly of mesogenic rod building blocks with terminally attached polyether
coils. This unique phase behavior seems to originate from a combination of or-
ganizing forces. These include the mutual repulsion of the dissimilar blocks
and packing constraints imposed by the connecting of each block, and the