Second-order nonlinear optical (NLO) polymers containing perfluoroaromatic rings as isolation groups with Ar/ArF self-assembly effect: Enhanced NLO coefficient and stability

Four new polyaryleneethynylenes P1–P4, which contained different aromatic or perfluoroaromatic isolation groups, were successfully prepared, via the palladium-catalyzed Sonogashira coupling reaction. Among them, P2, due to the presence of the self-assembly effect between the perfluoroaromatic and chromophore moieties, demonstrated much larger NLO effect (d33 value of 162.3 pm/V) and better stability with onset temperature for decay (111 °C). The research on the polymer conformation suggested that perfluorophenyl groups in different positions would result in different effects on the NLO coefficient, providing some useful information for the design of NLO polymers with better performance.