Design and synthesis of organic optical nonlinear multichromophore dendrimers based on double-donor structures

Abstract

The development of electro-optic materials with both large electro-optic coefficients and stability has always been the most challenging topic in this field. A series of chromophores C1–C3 based on the same bis(N,N-diethyl)aniline donor and tricyanethyldihydrofuran acceptor with isophorone-derived bridges were developed. Two-arm dendrimer C2 and three-arm dendrimer C3 were synthesised and evaluated compared to one-chromophore-containing dendritic material C1. This is the first time that a bis(N,N-diethyl)aniline-based donor has been used in CLD-type chromophores and a multichromophore system. Compared to chromophore C1, multichromophores C2 and C3 show much higher electro optic coefficients and glass transition temperatures. A large r₃₃ (180 pm V⁻¹) and poling efficiency (1.94 ± 0.08 nm² V⁻²) at 1310 nm have been achieved for neat films containing chromophore C2. Moreover, the glass transition temperature of dendrimer C2 was as high as 122 °C. The large electro-optic coefficient and strong stability make this material very promising in commercial applications.