Institute of Photonic Technology Jena e.V. Albert-Einstein-Str. 9, 07745 Jena, Germany.
Chemphyschem. 2013 Jan 14;14(1):170-8. doi: 10.1002/cphc.201200545. Epub 2012 Aug 31.
A spectroscopic characterization of polymers containing rigid π-conjugated oligo(phenyleneethynylene) chromophores as well as oligo(phenyleneethynylene) and methyl methacrylate is presented. The polymers exhibit molar masses of up to 15,000 g mol(-1) and a degree of polymerization between 22 and 80. Emission measurements of the monomeric and polymeric species show that radiative as well as nonradiative rates are influenced by the degree of polymerization due to intramolecular interactions of chromophores pendant to the polymer backbone. Time-resolved emission anisotropy measurements suggest that energy migrates within the polymers. Steady-state emission anisotropy measurements also point to energy migration. Additionally, two oligo(phenyleneethynylene)s with different sizes of the conjugated system are copolymerized in order to enable energy trapping due to energy transfer. The shortened energy-donor fluorescence lifetime within the donor-acceptor copolymers suggest energy transfer. Depending on the degree of polymerization, dispersion of the donor fluorescence lifetime is observed.
本文对含有刚性π共轭寡聚（苯乙炔）发色团以及寡聚（苯乙炔）和甲基丙烯酸甲酯的聚合物进行了光谱特性研究。这些聚合物的摩尔质量高达 15000 g/mol，聚合度在 22 到 80 之间。单体和聚合物物种的发射测量表明，由于发色团与聚合物主链上的侧基之间的分子内相互作用，辐射和非辐射速率都受到聚合度的影响。时间分辨发射各向异性测量表明能量在聚合物内迁移。稳态发射各向异性测量也表明能量迁移。此外，为了由于能量转移而实现能量捕获，将两种具有不同共轭体系大小的寡聚（苯乙炔）共聚。在供体-受体共聚物中，由于能量转移，缩短的供体荧光寿命表明能量转移。根据聚合度的不同，观察到供体荧光寿命的分散。
