Methoxyaniline-based binary crosslinkable chromophores for high-performance organic electro-optic thin films

Organic electro-optic materials are regarded as core candidates for next-generation co-packaged optics and AI high-speed optical interconnection systems, yet their practical applications are hindered by the trade-off between electro-optic activity and thermal stability. In this work, a series of binary crosslinkable chromophores (LD1–LD4) was designed and synthesized using methoxyaniline derivatives as electron donors. Orthogonal crosslinking sites for the anthracene/maleimide Diels–Alder reaction and azide–alkyne Huisgen cycloaddition were introduced into the molecular framework, enabling the construction of rigid covalent networks. The resulting crosslinked thin films exhibit a high glass transition temperature of 148–152 °C and an electro-optic coefficient of 213–267 pm V−1. Long-term high-temperature aging tests demonstrate that the poled films maintain over 89.9% of their initial orientation after 500 h of operation at 85 °C. Compared with previously reported aniline- and tetrahydroquinoline-based binary crosslinking materials, the LD series achieves balanced high performance, simplified synthetic routes and reduced costs.