Main-chain second-order nonlinear optical polyaryleneethynylenes containing isolation chromophores: enhanced nonlinear optical properties, improved optical transparency and stability

In this paper, five nitro azo chromophore based main-chain second-order nonlinear optical (NLO) polyaryleneethynylenes are successfully prepared, in which isolation chromophore moieties (sulfonyl ones) with different concentrations were introduced to improve the poling efficiency of the resultant polymers. Thanks to the effect of the isolation chromophore, P5 exhibited the largest d33 value of 111.1 pm V−1 as well as the best thermal stability and optical transparency, indicating that the isolation chromophore moieties could alleviate the "nonlinearity-stability trade off" and "nonlinearity-transparency trade off" in the NLO area efficiently.