Anisotropic networks and gels formed by photopolymerisation in the ferroelectric state

Abstract

Anisotropic networks are obtained by in situ photopolymerisation of liquid crystal (LC) molecules with reactive end groups in the macroscopically oriented state. Such cross-linked networks show high thermal stability and have passive electrical and optical applications. In situ polymerisation of LC reactive molecules in the presence of non-reactive LC molecules on the other hand leads to the formation of anisotropic gels. As opposed to the anisotropic networks, gels can be switched under the influence of electric fields and can therefore be used in display applications. In this review, a short introduction will be given to the technique of in situ photopolymerisation and ferroelectricity in LC. Subsequently various properties and various applications of anisotropic gels and networks obtained in the ferroelectric state will be described.

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