Syntheses and second-order nonlinear optical properties of a series of new “H”-shape polymers

To develop more “H”-shape nonlinear optical polymers, in this paper, four new polymers embedded with “H”-type chromophore moieties were designed and synthesized through a Suzuki coupling copolymerization reaction. The “H”-type chromophores were easily prepared by the utilization of “Click Chemistry” reactions, and their structures could be conveniently adjusted by changing the diazido groups. All the polymers exhibited good film-forming ability, thermal stability, and large optical nonlinearities. As a typical example, P4 demonstrated the highest d33 value of 94.7 pm/V, and its onset temperature for decay was up to 103 °C, making it promising candidate for practical applications in photonic fields.

► We attempted to adjust the linking bridge in the “H”-type chromophores to control the NLO performance of the resultant polymers, according to the concept of “suitable isolation group”.
► The popular “click chemistry” method is applied to the adjustment of the subtle structure.
► The resultant polymers embedded with such “H”-type chromophores show very good NLO activities.