Synthesis And Characterization Of Poly(Aryleneethynylene) Derivatived Conjugated Polymers

Poly(aryleneethynylene)s (PAEs) have drawn widespread interest in the past years due to their high stability, photophysical and non-linear properties. PAEs attractive promising prospect in a variety of applications, such as non-linear optics, semiconductors, sensors, and light-emitting devices(PLEDs). PAEs are a class of conjugated polymers in which aryl groups are connected by alkyne units. While unsubstituted PAEs are intractable, soluble derivatives can be obtained by attaching alkyl or alkoxy side chains to polymers'backbones. In this paper, we synthnsised aryleneethynylene bearing of different alkoxy side chains by palladium-catalyzed Sonogashira coupling , and prepared different poly(aryleneethynylene) derivatives containing 2,1,3-benzoselenadiazole group, 2,1,3-benzothiadiazole, quinoxaline, dichlorobenzophenone. Here we will disscuss as follow:Poly(aryleneethynylene) derivatives containing 2,1,3-benzoselenadiazole group and bearing side chains of different lengths, have been synthesized by palladium- catalyzed Sonagashira reaction. All of these polymers showed good solubility in common organic solvents and good film-forming capability.The third-order non-linear optical behavior of typical polymer PBS-C12 was also investigated here and the third -order nonlinear optical index of this polymer is 3.54×10-12 esu.Poly(aryleneethynylene)s (PAEs) are well-known and thoroughly investigated, however heterocyclic PAEs have been less explored despite the expectation of these materials to behave differently. Polymer which have electron-donor and electron- acceptor group now attract much attention, for it can result in decreased band gaps and more balanced charge carrier injection. We have synthesized a low-band-gap heterocyclic polymers containing benzoselenadiazole group and benzothiadiazole, and discussed charge transfer in these copolymer. Moreover, the PL quantum yilds (Φ_f ) of one chosened polymer PBT-10 in dilute chloroform solution (the absorbance of the solution would be lower than 0.1 A) was measured, theΦ_f value of PBT-10 is 29%. (9,10-diphenyl anthracene,cyclohexane as standard).In contrast to the successful utilization of PAEs in photoluminescence (PL) applications, there is not much satisfaction with the performance of (PLEDs) using PAEs as emissive materials. One factor responsible for the poor performance of PAEs-based PLEDs is the aggregate formation of polymer chains due to the rigid-rod feature of PAEs, which resulting in significant reduction of the fluorescence quantum yilds. Here we prepared Poly(aryleneethynylene)s containing large conjugated unit , such as quinoxaline and studied the influences on emissive property, and also measu -red the PL quantum yilds (Φ_f ) of one chosened polymer PQX-10 in dilute chlorofor -m solution (the absorbance of the solution would be lower than 0.1 A), theΦ_f value of PQX-10 is 24% (9,10-diphenyl anthracene,cyclohexane as standard).