Main chain dendronized hyperbranched polymers: convenient synthesis and good second-order nonlinear optical performance†
Abstract
By utilizing low generation dendrimers containing nitro based azo chromophore moieties as the macro-monomers, two second-order nonlinear optical (NLO) main chain dendronized hyperbranched polymers, PG1 and PG2, were prepared with satisfying yields by a one-pot “A3 + B2” approach via Suzuki coupling polymerization. Similar to most dendritic macromolecules, PG1 and PG2 possess good solubility and processability. More excitingly, with respect to the NLO performance, these two main chain dendronized hyperbranched polymers inherit the advantages of both dendrimers (large NLO coefficient) and hyperbranched polymers (good stability of NLO effects). In comparison with the dendrimers with a similar structure, both PG1 and PG2 demonstrate similar NLO coefficients but much more stable NLO effects.