(Photo)crosslinkable Smectic LC Main-Chain Polymers

✍ Scribed by Patrick Beyer; Lydia Braun; Rudolf Zentel

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 221 KB
• Volume: 208
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200700292

✦ Synopsis

Abstract

This paper presents the synthetic route to SmA LC main‐chain polymers, that can be (photo)crosslinked without solvent in the bulk phase. They are based on soluble polymalonates, in which higher ordered phases can be suppressed by copolymerization with a laterally brominated biphenyl. Two routes were developed to incorporate the crosslinkable groups into the polyester backbone. The first consists in the incorporation of phenols into the polyester. These phenols are not reactive enough to participate in the transesterification reaction used to build up the polymer, but they can be esterified afterwards with acrylates. Thermally or photochemically created radicals then start the crosslinking. The second route is based on the incorporation of benzophenone as side group. It allows a photochemical crosslinking. Crosslinked fibers (monodomains) show the potential of the smectic LC main‐chain elastomers as actuators.

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