Polyoxadiazoles properties

Polysulfanyldibenzamides Polyhydrazides Melting points up to 330°C (626°F) soluble good fiber properties Dehydrate at 200°C (392°F) to over 400° C (752°F) to form polyoxadiazoles good fiber properties. 

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... 

Polycyclic oxadiazoles linked to phenyl groups have been prepared. Table 8 compares their physical properties with those of the corresponding polyphenyls the solubility of polyoxadiazoles in organic solvents is much higher and their melting point is lower 18 a). 

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. 

The fibers of aromatic PODs are known to have a combination of good properties, such as strength and stiffness, fatigue resistance, and relatively low density, in the range of 1.2 to 1.4 g/cm3. PODs have been used to improve the heat resistance of many synthetic fibers. This is usually done by dissolving the POD in sulfuric acid and then treating the fibers with this solution. Poly( >-phenylene-l,3,4-oxadiazole) is the most commonly used commercial polyoxadiazole, and the fiber spun from this polymer is called Oksalon. 

Hensema ER, Boom JP, Mulder MHV, Smolders C A. Two reaction routes for the preparation of aromatic polyoxadiazoles and polytriazoles syntheses and properties. J Polym Sci Part A Polym Chem 1994 32(3) 513-25. 

Yasujima H, Murakami M, Yoshimura S. Electrical properties of pyrolytic polyoxadiazole. Synth Met 1987 18(l-3) 527-30. 

Detailed studies on the influence of an increasing ENR content on the thermal stability of PVC/ENR blends have also been reported. Other evidence vas obtained by Calandrelli and co vorkers [17], who improved the thermal properties of the aromatic polyoxadiazole by blending it with a secondary homopolymer component, polyamide. 

Keywords Polyoxadiazole, molecular weight, mechanical properties, thermal stability, sulfonation, composites, coating, corrosion, fuel cell, PEMFC, proton conductivity, carbon nanotubes... 

Figure 2.7 Tensile properties of polyoxadiazole samples as a function of molecular weight...

Figure 2.8 Tensile properties of high performance polymers (SPODDPE, sulfonated polyoxadiazole PEEK, polyfether ether ketone) PES, poly(ether sulfone) Vespel , Poly(pjromellitimide-l,4-diphenyl ether) Torlon , poly(amide imide) Ultem , polyfether imide) LaRC, aromatic poly(imide) [34,35],...

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