Development And Photophysical Properties Of Ln³⁺-containing Metallopolymers

The characteristic emissions of lanthanide ion including Eu³⁺,Tb³⁺,Nd³⁺, Yb³⁺+ or Er³⁺, such as large Stokes shift, micro-to millisecond-grade long lifetime and narrow line-like luminescence, have been concerning due to their potential applications in organic light emitting diodes ?OLEDs?, white light-emitting materials, optical communications, laser materials and fluorescent immunoassay, respectively. On the one hand, from the viewpoint of the remaining challenge to a persuit of high quantum yield, both the well-matched energy levels between triplet energy level of "antenna" groups and the first excited state energy level of the corresponding lanthanide ion and the avoidance of CH-, NH-and OH-vibrated quenching are required. On the other hand, in view of their practical applications as an ideal opto-electronic material, some other physical properties including high thermal stability, excellent filmforming ability and good mechanical strength are expected. For this context, an effect approach is to grafting the small molecule Ln³⁺- complex into one of polymeric matrix through covalent bonds, leading to new Ln³⁺ -containing metallopolymers.Based on a worthwhile method to coordination and post-polymerization, series of different Ln³⁺-containing (Eu³⁺?Tb³⁺?Nd³⁺?Yb³⁺or Er³⁺), different polymeric matrix ?PMMA or PNBE?, mixed-Ln³⁺-containing (Eu³⁺and Tb³⁺ or Nd³⁺ and Yb³⁺), and PMMA- and PNBE-supported Ln³⁺ -containing metallopolymers were constructed, in which, both high luminous efficiency and good physical properties are anticipated. Details are shown as follows:1. Based on the difference of Eu³⁺, Tb³⁺, Nd³⁺, Yb³⁺ or Er³⁺ ion, series of homoleptic Ln³⁺ -containing metallopolymers with various luminescent properties were obtained, respectively, where Eu³⁺-centered color-purity red-light one, cyan-light emitting one combined from ligand-centered blue-light with Tb³⁺ -centered color-purity green-light, infrared-red luminescent one with Nd³⁺,Yb³⁺ or Er³⁺ ion were concerned.2. Based on the difference of polymerization mechanism, series of PMMA-or PNBE-supported Ln³⁺ -containing metallopolymers were obtained, respectively, where the involvement of flexible allyl groups led to the polymerization its Ln³⁺ -complex monomer with NBE ?norborene? in the presence of H-Grubbs II catalyst by the ring-opening copolymerization while failed to radical polymerization with MMA ?methyl methacrylate? in activation with AIBN. However, from the polymerization of the Ln³⁺-complex monomer with active vinyl groups with either NBE in the presence of H-Grubbs II catalyst by the ring-opening copolymerization or MMA in the presence of AIBN by the radical copolymerization, the series of PMMA-or PNBE-supported Ln³⁺-containing metallopolymers could be obtained, respectively.3. Through the design of the Ln³⁺-complex monomer with both allyl and vinyl groups, the first example of PNBE-and PMMA-supported while grafting-type Ln³⁺-containing metallopolymers were prepared.4. Through the terpolymerization of Nd³⁺-complex monomer, Yb³⁺-complex monomer and MMA or Eu³⁺-complex monomer, Tb³⁺-complex monomer and MMA, the two series of single-component while mixed-Ln³⁺-containing metallopolymers were obtained, respectively. From the adjustment of mixed-Ln³⁺concentrations, the single-component while Nd³⁺-Yb³⁺-containing metallopolymer with dual Ln³⁺-centered NIR luminescence could be applied as barcode materials, and the single-component while Eu³⁺-Tb³⁺-containing metallopolymer exhibited an ideal white-light luminescent property.5. With the single-component while Eu³⁺-Tb³⁺-contributed white-light metallopolymer as the luminescent layer material, the WPLED was constructed and its electroluminescent propery was also explored.