含溴橙光化合物与双(三环己基膦)钯(0)进行氧化加成反应,合成了相应的芳基钯(Ⅱ)配合物.在加热条件下,该配合物可以引发AB型芴单体聚合,得到端基为橙光芳基基团的聚芴共轭聚合物.含溴橙光化合物与不同配体钯(0)配合物组成催化体系,原位引发聚合,同样可以制备上述端基结构明确的共轭聚合物.其中,以三(邻甲基苯基)膦或卡宾化合物为辅助配体时,室温下即可引发AB型芴单体进行催化剂转移聚合.卡宾化合物为辅助配体时,可以获得Mn为7.48×10^4的高分子量聚芴.MALDI-TOF分析证实,聚合物的一个端基是来自催化剂钯配合物中的橙光芳基基团,另一端基为Br/H原子.聚合物光致发光(PL)光谱主要表现为聚芴单元的蓝色荧光发射.电致发光(EL)光谱表明,聚合物在低分子量时表现为橙红光发射,而在高分子量时,能够得到白光发射.在数均分子量Mn为7.48×10^4时,聚合物可实现纯白光发射,国际色坐标CIE为(0.31,0.32).
An Aryl palladium complex was synthesized by oxidative addition of aryl bromide-containing orange emissive group (OG-Br) to Pd (PCy3)2. The complex is thermally stable in air and can initiate the polymerization of AB-type fluorene monomer at elevated temperature to get polyfluorene with defined aryl end group. Similar conjugated polymers can also be prepared by employing the aryl palladium complexes in situ generated from OG-Br/Pd(0)-species as initiators. Among them, with P (o-tol)3 or N-heterocyclic carbene as the ancillary ligand, catalyst-transfer polymerization of AB-type fluorene monomers can be achieved at room temperature. The complex ligated by N-heterocyclic carbene shows better activity in the catalyst-transfer polymerization ,which offer the polyfluorene with high molecular weight of up to 7.48 × 10^4. MALDI-TOF mass spectra confirm that the polymers bear the orange emissive group derived from the aryl complex at one end and a Br/H atom at the other end. Photoluminescence (PL) spectra of the polymers show dominant blue emission from the polyfluorene backbone. In contrast, electroluminescence (EL) spectra exhibit orange or white emission,respectively,resulting from a difference of the molecular weight. With the number average molecular weight (Mn) of 7.48 × 10^4 , the polymer emits pure white light with simultaneous blue and orange emission and CIE coordinates of (0.31,0.32).