Poly triazole

Composite membranes containing 1,2,4-poly triazoles were previously prepared by Jones et al. (2) and used in fuel cells. 

B. Gebben. Thermally stable and chemically polymer membranes-aromatic polyoxadiazoles and poly triazoles. PhD thesis, Twente University, Enschede, Holland, 1988. 

Oxamidrazone, NHj—NH—C(NH)—C(NH)—NH—NH2, is produced from dicyan and hydrazine, and its isomer converted with terephthaloyl chloride to poly(terephthaloyl oxamidrazone), PTO. PTO can be converted to a poly(triazole), a poly(oxadiazole), or to a metal ion chelated polymer ... 

Poly(triazoles) and poly(oxadiazoles), each with two hetero rings per repeat unit, are obtained by the process described in the previous section. Poly(triazoles) with one triazole residue per structural element are produced from terephthalic acid and hydrazine with subsequent cyclocondensation of... 

The poly(triazole) produced has a very high glass transition temperature of 260 C. It can be wet or dry spun from formic acid. The fibers still retain 30% of their original elongation at break even at 300 C. But to obtain poly(oxadia-zole) fibers, poly(phenylene hydrazide) is spun. Water is eliminated from their drawn or undrawn fibers to produce poly(oxadiazole) fibers. 

The thermal behavior of nanocomposites films based on poly(triazole-imide) reinforced with neat and modified SiC nanoparticles was investigated [85]. The nanocomposites decomposition temperatures increased with SiC content, indicating an enhancement of the thermal stability in the presence of SiC. Moreover, the char yield increased from 58 % for the poly(triazole-imide) to 85 % for the nanocomposites containing 10 % SiC. The nanocomposites containing SiC nanoparticles functionalized with epoxide-end groups showed a lower thermal stability compared to the nanocomposites containing neat SiC. 

An interesting class of metal-induced cross-linking gel was reported by Hecht [68]. A poly(triazole-pyridine) 68 was prepared by AABB CuAAC copolymerization of a pyridyl diacetylene 69 and a chiral aryl diazide 70 (Scheme 20). Due to the repulsive interactions between the nitrogen lone-pair electrons on the triazole and pyridine units [69], the polymer tended to adopt a helical conformation in the absence of metal ions. On the other hand, metallogels 71 were formed when Zn (II), Fe(II), or Eu(III) ion was added to a solution of the polymer in acetonitrile. It was believed that the 2,6-bis(triazolyl)pyridine ligands chelated to the metal ion to form a hexacoordinate metal complex, which then led to a metal-promoted cross-linked 3D network that entrapped acetonitrile solvents. 

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