Synthesis of laterally attached side‐chain liquid‐crystalline polynorbornenes with high mesogen density by ring‐opening metathesis polymerization

(±)-exo,endo-5,6-Bis{[[11′-[2″,5″-bis[2-(3′-fluoro-4′-n-alkoxyphenyl)ethynyl]phenyl]undecyl]oxy]carbonyl}bicyclo[2.2.1]hept-2-ene (n = 1–12) monomers were polymerized by ring-opening metathesis polymerization in tetrahydrofuran at room temperature with Mo(CHCMe2Ph)(N-2,6-iPr2Ph)(OtBu)2 as the initiator to produce polymers with number-average degrees of polymerization of 8–37 and relatively narrow polydispersities (polydispersity index = 1.08–1.31). The thermotropic behavior of these materials was independent of the molecular weight and therefore representative of that of a polymer at approximately 15 repeat units. The polymers exhibited an enantiotropic nematic mesophase when n was 2 or greater. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4076–4087, 2006

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