Synthesis and properties of novel poly(meth)-acrylates containing tricyanocyclopropyl groups for piezoelectric applications

o‐(2,2,3‐Tricyano‐3‐carbomethoxycyclopropyl)phenoxyethyl acrylate (5a) and o‐(2,2,3‐tricyano‐3‐carbomethoxycyclopropyl)phenoxyethyl methacrylate (5b) were prepared by reactions of bromomalononitrile with methyl o‐(2‐acryloyloxyethoxy)benzylidenecyanoacetate and methyl o‐(2‐methacryloyloxyethoxy)benzylidenecyanoacetate respectively. The dipole moments of 5a and 5b, calculated by atom superposition and electron delocalization molecular orbital method, were 2.75–3.47 D. Monomers 5a and 5b were polymerized with free‐radical initiators to obtain the polymers with tricyanocyclopropane ring as a piezoelectric chromophore in the pendant group. The resulting polymers 6a and 6b were soluble in common organic solvents such as acetone and DMF. Polymers 6a and b showed thermal stability up to 280 °C in TGA thermograms. Tg values obtained from DSC thermograms were in the range 125–140 °C. Piezoelectric coefficients (d31) of the poled films were 1.2–1.4 pC N−1. These polymers showed good temporal and long‐term thermal stabilities which are acceptable for piezoelectric device applications. Copyright © 2003 Society of Chemical Industry