Novel cross-linked chromophores based on Diels-Alder reaction or Huisgen reaction

Abstract

In order to synthesize binary crosslinked materials with both high electro-optic coefficient and high long term alignment stability, reaction was developed for making binary crosslinkable materials WLD1-4 and single component cross-linked material WLD5 using traditional aniline as the donor. The crosslinking reaction that occurs after the completion of molecular poling orientation converts small molecule into polymer materials which greatly improving the glass transition temperature and stability of the materials. The high density of chromophores (5.55-6.01 × 1020 molecules/cm3) and first-order hyperpolarization result in a large electro-optic coefficient up to 190-237 pm/V at 1310nm. And the glass transition temperature of the material also rises from the initial 51-75 °C to 117-144 °C after crosslinking. We also tested the long-term stability of the cross-linked material at high temperatures, The results indicate that after heating at 85 °C for over 500 h, more than 85% of the initial r33 value was maintained for poled and crosslinked electro-optic films WLD5. These structures further expand the design concept of pure chromophore crosslinked materials and lay a solid foundation for commercial organic electro-optic materials.