Liquid crystalline polymers mesogenic group

Reck, B., and Ringsdorf, H. Combined Liquid Crystalline Polymers Mesogens in the Main Chain and as Side Groups. Makromol. Chem., Rapid Commun. 6, 291 (1985). 

In side group type liquid crystalline polymers, mesogenic units attach to the main chain in two basic ways, i.e., by end attachment (end-on) or by side attachment (side-on). Most polymers studied are of the end-on type. The side-on type is relatively new and only a few systems have been studied. However, because the latter polymers have displayed unusual structure and property, they are discussed separately in Section 3.6. 

Scherowsky G, Fichna U, Wolff D (1995) Ferroelectric liquid-crystalline polymers side-group derived from mesogenic vinyl ether monomers. Liq Cryst 19(5) 621-627. doi 10.1080/... 

Shibaev, V. P. and Plate, N. A. Thermotropic Liquid-Crystalline Polymers with Mesogenic Side Groups, Vol. 60/61, pp. 173—252. 

Fig. 29. Observed and calculated 2H NMR spectra for the mesogenic groups of a) the nematic (m = 2), b) the smectic (m = 6) liquid crystalline polymer in the glassy state, showing the line shape changes due to the freezing of the jump motion of the labelled phenyl ring. The exchange frequency corresponds to the centre of the distribution of correlation times. Note that the order parameters are different, S = 0.65 in the frozen nematic, and S = 0.85 in the frozen smectic system, respectively...

In summary the results of our 2H NMR investigation illustrate the spacer model for liquid crystalline polymers, indicating, however, that the decoupling of the mesogenic groups from the main chain, while effective, is not complete. 

Liquid-crystalline polymer consisting of macromolecules in which mesogenic groups are incorporated both in the main-chain and in the side-groups. 

Finkelmann, H., Happ, M., Portugal, M. and Ringsdorf, H. Liquid crystalline polymers with biphenyl-moieties as mesogenic group. Makromol. Chem. 179, 2541 (1978)... 

Thermotropic Liquid-Crystalline Polymers with Mesogenic Side Groups... 

Thus, the remoteness of mesogenic groups from the backbone provided by a polymethylene spacer secures them sufficient autonomy from the main chain. On the other hand, the fact that mesogenic groups are chemically linked with the main chain of the macromolecule assists their cooperative interaction. This is why comblike polymers have come to be accepted as convenient matrices for constructing LC polymers. Already a few hundred liquid-crystalline polymers with various mesogenic side groups have been synthesized. 

Table 1. Some types of liquid-crystalline polymers with mesogenic side groups...

---