Non-amphiphilic

Note 2 The mesomorphic character of a lyotropic mesophase arises from the extended, ordered arrangement of the solvent-induced micelles. Hence, such mesophases should be regarded as based not on the structural arrangement of individual molecules (as in a non-amphiphilic or a thermotropic mesophase), but on the arrangement within multimolecular domains. 

Note 1 At one time it was thought that a non-amphiphilic molecule had to be long and rod-like for mesophase formation, but it has now been established that molecules of other types and shapes, for example, disc-like and banana-shaped molecules, may also form mesophases. (See ref. 6). 

Winsor, P. A. Non-amphiphilic cubic mesophases plastic crystals . Chapter 2.2 in Ref. 15b... 

Attaching non amphiphilic or amphiphilic liquid crystalline molecules as side chains to linear, branched or crosslinkedpolymers yields liquid crystal (l.c.) side chain polymers, which can exhibit the liquid crystalline state analogously to the conventional low molar mass liquid crystals. The l.c.-side chain polymers combine the specific, anisotropic properties of the liquid crystalline state with the specific properties of polymers. 

The systematic synthesis of non amphiphilic l.c.-side chain polymers and detailed physico-chemical investigations are discussed. The phase behavior and structure ofnematic, cholesteric and smectic polymers are described. Their optical properties and the state of order of cholesteric and nematic polymers are analysed in comparison to conventional low molar mass liquid crystals. The phase transition into the glassy state and optical characterization of the anisotropic glasses having liquid crystalline structures are examined. 

In the first part of this paper we will give a review on our experimental work on non amphiphilic l.c. side chain polymers and will compare their properties with the corresponding l-l.c. s. In the second part results on amphiphilic side chain polymers will be discussed. 

Non Amphiphilic L.C. Side Chain Polymers 2.1 Model Considerations and Synthesis... 

Generic Relationships between Non-Amphiphilic and Amphiphilic Mesophases of the "Fused Type... 

Relationship of Cubic Mesophases ("Plastic Crystals ) Formed by Non-Amphiphilic Globular Molecules to Cubic Mesophases of the Amphiphilic Series... 

T he purpose of this account is to point out certain generic relationships between the mesophases of the non-amphiphilic series—nematic,... 

The cubic amphiphilic mesophases (Sic, Vi, and V2) from their interposition in the succession of mesophases Sic, Mi, Vi, G, V2, and M2, have generally been termed liquid crystalline like the optically anisotropic amphiphilic mesophases Mi, G, and M2. The cubic mesophases formed by non-amphiphilic globular molecules have however usually been termed plastic crystals. This nomenclature has obscured the fact that these plastic crystals are fundamentally liquid crystals rather than solid cyrstals and bear a relationship to the optically anisotropic non-amphiphilic smectic and nematic liquid crystals similar to that born by the amphiphilic cubic mesophases to the optically anisotropic neat (G) and middle (Mi and M2) liquid crystalline phases. 

In the non-amphiphilic smectic A mesophase (Figure 2b), the parallel, fairly rigid, lath-like molecules are grouped with orientational disorder (at right angles to their long axes) and end-to-end so that the molecules lie statistically normal to the sheets, constituting an optically uniaxial... 

Non-Amphiphilic Cubic Mesophases Plastic Crystals. The cubic plastic crystals of the non-amphiphilic series, to which the amphiphilic... 

Table II. Crystalline Forms of Some Non-Amphiphilic Plastic Crystals (23,24) and of Some Amphiphilic Cubic Mesophases...

One feature of the non-amphiphilic cubic mesophases is that they frequently show mutual miscibility even when constituted from dissimilar molecules. Such miscibility, which contrasts with the immiscibility between dissimilarly constituted solid crystals, is also found between nematic mesophases, between corresponding smectic polymorphs, and, of course, between amorphous liquids. This miscibility is important in its implication that in the cubic mesophases of the amphiphilic series there could well be an equilibrium of related globular micellar forms (Figures 1 and 5) rather than a single clearly defined form. 

An important characteristic of the cubic mesophases, either non-amphiphilic or amphiphilic, is that because of the fairly free thermal rotational motions of their constituent units, they typically give high resolution NMR spectra. In this respect they behave like amorphous liquids and quite differently from conventional solids or from mesophases such as Mi, M2, or G in which rotation of the units is more severely restricted. 

Formation of the Vi and V2 Mesophases and of the Non-Amphiphilic Cubic Mesophase "Smectic D . In Figures 1 and 5, the formation of the amphiphilic cubic mesophases Vi and V2 is attributed to transitional globular micellar forms which arise intermediate between the indefinitely extended fibrous (M) and lamellar (G) forms which constitute the middle and neat mesophases, respectively. With a few non-amphiphilic mesogens (19, 20, 21, 22) a cubic mesophase "smectic D is found intermediate in the thermal succession of mesophases between smectic A... 

The aggregates discussed above are all anisodimensional, which is the reason for the anisotropic character of the mesophases. In some systems it has been possible to prove the existence of isotropic highly viscous phases of similar structure but which clearly consist of almost isodimensional aggregates. The exact structure of these phases is still the subject of discussion, as is also the case with the complex mesophases. The relation between the isotropic phases and globular proteins and plastic crystals of non-amphiphilic substances has been discussed by Gray and Winsor (5). 

Balaz and Lukacova (1999) attempted to model the partitioning of 36 non-ionizable compounds in 7 tissues. Amphiphilic compounds, or those possessing extreme log Kow values, tended to show complex distribution kinetics because of their slow membrane transport. However for the non-amphiphilic, non-ionizable compounds with non-extreme log Kow values studied it should be possible to characterize their distribution characteristics based on tissue blood PCs. Distribution is dependent on membrane accumulation, protein binding, and distribution in the aqueous phase. As these features are global rather than dependent on specific 3D structure, distribution is not expected to be structure-specific. In this study, tissue compositions in terms of their protein, lipid, and water content were taken from published data. This information was used to generate models indicating that partitioning was a non-linear function of the compound s lipophilicity and the specific tissue composition. 

Bhattacharya and Snehalatha also examined the reactivities of both functionalized DAAP surfactants and simple non-amphiphilic DAAP analogues in microemulsion droplets and found that their reactivities were quite altered in such aggregates when compared with their reactivities in micellar media [23-24]. 

More recently, micelle formation of non-amphiphilic BCs in non-selective solvents in which both blocks are soluble has been reported [32]. In this case,... 

In order to understand the basic principles of operation of the many different kinds of LCDs being developed and/or manufactured at the present time, it is necessary to briefly describe the liquid crystalline state and then define the physical properties of direct relevance to LCDs. First, the nematic, smectic and columnar liquid crystalline states will be described briefly. However, the rest of the monograph dealing with liquid crystals will concentrate on nematic liquid crystals and their physical properties, since the vast majority of LCDs manufactured operate using mixtures of thermotropic, non-amphiphilic rodlike organic compounds in the nematic state. 

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