Mild and in situ photo-crosslinking of anthracene-functionalized poly (aryl ether ketone) for enhancing temporal stability of organic NLO materials

Developing a mild and efficient method to simultaneously enhance poling efficiency and temporal stability is meaningful and challenging for organic second-order nonlinear optical materials. In this paper, a new poly (aryl ether ketone) and chromophores functionalized with anthracene groups have been designed and prepared. Poling and crosslinking process could be separated by the mild and photo-initiated cycloaddition of anthracene group. As the UV–Vis spectrum, DSC and TGA curves, the networks had formed by 30-min irradiation of the Lower-power UV light which led little decomposition of dipolar chromophores. The maximum electro-optic coefficient (r33) of these polymers is 28.5 pm V−1 (at 1.3 μm), and the order parameter reaches 0.22. Moreover, the depolarization temperature of α peak, related to the dipole relaxation, has been increased to 129 °C after crosslinking, which is 17 °C higher than uncrosslinked ones. All these results indicated that the photo-crosslinking of anthracene exhibited promising potential for improving alignment stability and NLO activity at the same time.