Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Functionalized mesogens

Beside the synthesis of linear polysiloxanes, hydrosilylation was also nsed to obtain liquid crystalline elastomers. This can be performed in two ways, either a one pot reaction involving a diolefln together with the functionalized mesogen or a two step process involving first the synthesis of a linear polysiloxane, bearing adequate functions for a further crossfinking. For example, a photosensitive group such as benzophenone could be introduced (Fig. 5, x and y are theoretical values). In order to ensure a full conversion in silane, the time of reaction was increased here to 65 h [17]. [Pg.141]

Another type of supramolecular side-chain polymers (shown in Fig. lOB) is obtained by the complexation of functionalized mesogenic molecules with polymer backbones. The hydrogen-bonded complex of 37 is obtained by mixing poly(4-vinylpyridine) or poly(4-vinylpyridine-co-styrene) with mesogenic compounds terminated by a carboxylic acid moiety through a flexible spacer [84-88]. The hydrogen bonding between imidazole and carboxylic acid is also useful for the formation of supramolecular complexes. Polymeric complex 38 exhibits a smectic A phase from 10 to 65 °C [89]. [Pg.114]

Figure 3.19 Molecular components for ionic complexes of simple functional polymers and functionalized mesogens. Figure 3.19 Molecular components for ionic complexes of simple functional polymers and functionalized mesogens.
Figure 3.25 Representation of ionic complexes prepared from poly(ethylene imine) and carboxylic acid-functionalized mesogens. Figure 3.25 Representation of ionic complexes prepared from poly(ethylene imine) and carboxylic acid-functionalized mesogens.
Figure 3.27 Schematic representation comparing (a) an ionic complex of a cationic polymer and an anionically functionalized mesogen, (b) an ionic complex of a cationic polymer and an anionic surfactant, and (c) a polymer to which a mesogen is covalently attached at a cationic site neutralized by a counterion. Figure 3.27 Schematic representation comparing (a) an ionic complex of a cationic polymer and an anionically functionalized mesogen, (b) an ionic complex of a cationic polymer and an anionic surfactant, and (c) a polymer to which a mesogen is covalently attached at a cationic site neutralized by a counterion.
End-functionalized mesogenic molecules are used to form the second type of supramolecular side-chain polymers (Figure 2(a) [ii], Figure 23) [97-108], Polymeric complex 28 has been prepared based on poly(4-vinylpyridine) [97], The hydrogen-bonding formation between imidazole and carboxylic acid moieties yields supramolecular side-chain polymers of 29 [103], which exhibit smectic A phases. The interactions of carboxylic acid/dialkylamine [104-106], phenol/amine [107], and hydroxyl/pyridine [108] were used for the preparation of the side-chain mesogenic complexes. [Pg.149]

As indicated in Figure 8, the crosslinking of discotic monomers might lead to insulated wires. The crosslinking of diacetylene-functionalized mesogens via a topochemical polymerization in a columnar phase was reported, but no electronical charartetization was performed. ... [Pg.133]


See other pages where Functionalized mesogens is mentioned: [Pg.119]    [Pg.160]    [Pg.48]    [Pg.85]    [Pg.106]    [Pg.121]    [Pg.127]    [Pg.136]    [Pg.102]    [Pg.75]    [Pg.77]    [Pg.80]    [Pg.84]    [Pg.85]    [Pg.280]    [Pg.119]    [Pg.132]    [Pg.133]   
See also in sourсe #XX -- [ Pg.79 ]




SEARCH



Mesogen

Mesogenicity

Mesogens

© 2024 chempedia.info