Properties liquid crystal, polysiloxane with

Only relatively recently have lyotropic polymers been investigated with respect to their liquid crystal properties. In 1982 Finkelmann, Luhmann and Rehage synthesized a series of surfactants having 10-undecenoic acid as the hydrophobic region and a polyethylene glycol moiety as the hydrophilic region. The corresponding polymers were produced by addition of these surfactants to a polysiloxane main chain. The structure of the polymers is shown below ... 

Jt OLYSILOXANES WITH PENDANT SIDE CHAINS are interesting materials from both the theoretical and practical points of view. A number of polysiloxanes with various side chains, such as liquid crystals (i, 2), carbazole groups (3), electron-donor and electron-acceptor groups (4), polystyrene (5), and functional groups (hydroxyl or carboxyl) (6), have been synthesized. Polysiloxanes are known for their useful properties, which include flexibility, heat resistance, water repellence, and biological inertness. These properties, combined with the ease with which a tailored polymer structure can be prepared,... 

Subclass 02, biparallel structures. This class, with nematic structures, was obtained by Hessel and Finkelmann and called biaxial. While the word biaxial is quite appropriate, it is also used in the liquid crystal field in connection with structures of smectic C phases, hence a new name was proposed. A low-molecular-mass 02 compound was synthesized by Malthete and his colleagues. Properties of a polysiloxane with phenyl benzoate mesogens obtained by Finkelmann were studied by Hotz and Strobl. " ... 

It is very often the commercial interest in novel materials which stimulates the growth in their study and eventual exploitation. This is certainly true in the case of thermotropic liquid crystals and their application in electro-optic displays. Indeed, the production of high-strength, high-modulus fibres has seen a wealth of interest in lyotropic main chain polymers. The use of lyotropic side chain polymers has, by comparison, been less well publicized. This is not to say that there are no applications. Alkyl polyoxyethylene surfactants attached to polysiloxane polymers have found uses in many personal care products such as liquid soaps, shampoos, skin creams, and hair mousses. Unfortunately the physical properties of these and other similar materials have been closely guarded secrets and the amount of information available in the literature is low. The limited data which does exist, however, provides us with some interesting structure - behaviour relationships. 

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