Polyoxadiazoles synthesis

For this reason, the polyoxadiazole synthesis may present low reproducibility and different polymer materials may be produced at similar reaction conditions at actual lab-scale polymerization reactors [10]. These observed experimental fluctuations constitute a major drawback for the systematic use of polyoxadiazole in certain applications and for the design and scale-up of its synthesis. 

N.C. Yang, Y.H. Park, and D.H. Suh, Synthesis and properties of new ultraviolet-blue-emissive fluorene-based aromatic polyoxadiazoles with confinement moieties, J. Polym. Sci., Part A Polym. Chem., 41 674-683, 2003. 

Yang NC, Chang S, Suh DH (2003) Synthesis and optically acid-sensory properties of novel polyoxadiazole derivatives. Polymer 44 2143-2148... 

Synthesis and Properties. Polyoxadiazoles containing aromatic moieties with aliphatic linkages/groups have been widely explored in the literature. The aromatic moieties increase the rigidity of the polymer the presence of aliphatic groups makes the chain more flexible and processible. 

D. Gomes, S. P. Nunes, J. Carlos Pinto, and C. Borges. Synthesis and characterization of flexible polyoxadiazole films through cyclodehydration of polyhydrazides. Polymer, 44(13) 3633-3639, June 2003. 

Figure 4 shows the UV-VIS spectra of the polymers 13a, 13b, 14a-2,14b-l, 14b-2 and the photoluminescence spectrum of 14b-l. The polyoxadiazole synthesized by the one-pot synthesis (14b-l) has a smaller HOMO-LUMO gap (3.76 eV) compared with 14b-2 (3.87 eV). This implies that the one-pot reaction leads to a more fully converted polyaromatic oxadiazole than thermal conversion of the polyhydrazide precursor. 

E.R.Hensema, Polyoxadiazole and Polytriazole Gas Separation Membranes-Synthesis and Properties, Ph.D. Thesis, Twente University, Enschede, Holland, 991. 

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