Polybenzoxazoles synthesis

Hydroxyphenylimide, polybenzoxazole synthesis via, 318 Hydroxy-terminated hyperbranched polyesters, 32... 

Poly(2,5-benzophenone), synthesis of, 492 Polybenzothiazole, synthesis of, 314-319 Polybenzoxazoles, synthesis of, 292, 314-319... 

Figure 5.23 Synthesis of polybenzoxazoles by catalytic carbonylation of 4,4 -diiododi-phenylether.

Figure 5.47 Synthesis of polybenzoxazole with isolation of polyamide phenol intermediate.

Research Focus Synthesis of perfluoro polybenzoxazole derivatives for use in semiconductor devices. 

Furthermore, we have extended the high-pressure polycondensation to the synthesis of condensation polymers other than polyimides. A successful example was the high-pressure synthesis of polybenzoxazoles starting from the bis-o-aminophenol (or its hydrochloride) and aliphatic dinitriles (Eq. 8) [35]. The polycondensation readily proceeded under high pressure in a closed reaction vessel with the elimination of the by-product of ammonia (or ammonium chloride). 

W.D. Joseph, R. Mercier, A. Prasad, H. Maraud, J.E. McGrath, Synthesis of 4,4 -iso-propylidene diphenol (bisphenol A) based polybenzoxazoles via an acid-catalysed solution cyclization process. Polymer 34 (4) (1993) 866-869. 

Y. Maruyama, Y. Oishi, M.A. Kakimoto, Y. Imai, Synthesis and properties of fiuorine-containing aromahc polybenzoxazoles from bis(o-ami-nophenols) and aromahc diacid chlorides by the silylahon method. Macromolecules 21 (8) (1988)2305-2309. 

Y. Oishi, A. Konno, J. Oravec, K. Mori, Synthesis and properties of fiuorine containing polybenzoxazole by in-situ silylation method, Photopolym. Sci. Technol. 19 (5) (2(X)6) 669-672. 

In this paper we report the synthesis of new AB monomers which have potential for forming polybenzoxazoles with backbone alkane and alkene moities. Application to monomers of the previously developed low-temperature, high-yield condensation procedure (8) employing triphenylphosphine, hexachloroethane and pyridine is described. The soluble aryl-alkyl and aryl-alkenyl polyamides thus obtained were characterized and converted to polybenzoxazoles. Comparisons are presented between polymers obtained by this two-step method and those prepared by traditional methods. 

Some polymerizations of also gave insoluble materials, especially when the traditional one-step procedures were employed. Monomer 3 is the best example of the ability of the two-step synthesis to give high molecular weight polybenzoxazole. While the intermediate polyamide had an inherent viscosity of 0.25 dl/g, that of the final polybenzoxazole was 2.25 dl/g. Monomer 4 could... 

Hsu SL-C, Chang K-C (2002) Synthesis and properties of polybenzoxazole-clay nanocomposites. Polymer 43 4097 101... 

Overall goals of our research in this area include synthesis of thianthrene di-, tri- and tetracarboxylic acid derivatives (10,11,12,13 Figure 7) starting with 3,4-dichlorobenzoic acid and 4,5-dichlorophthalic acid evaluation of their use in formation of thianthrene-containing polyimides, aramids, and polybenzoxazoles and... 

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