High-temperature adhesives polyphenylquinoxalines

Polyphenylquinoxalines (PPQ) are easier to make than the polyquinoxalines and offer superior solubiHty, processibiHty, and thermooxidative stabiHty (65). The PPQs exhibit excellent high temperature adhesive, composite, and film properties. However, to increase the use temperature of PPQs, acetylene... 

Polyphenylquinoxalines (PPQ s) were first prepared in 1967 by Hergenrother (56). In 1975, Koval et al. (57,58) introduced the acetylene-terminated PPQ (ATPQ) (Pig. 10), which is the addition type of PPQ. Resembling ATPI, ATPQ also has shortcomings. The ethynl group hinders the flow of the polymer chain, and the cured ATPQ is less thermal-oxidatively stable than the comparable PPQ. The detailed status of PPQ, as well as other high-temperature adhesives, is discussed by Hergenrother (45). ... 

A serious limitation to the use of organic polymers in general and of adhesives, in particular, is their poor resistance to thermal degradation. Considerable effort has been put into the development of High-temperature adhesives and examples of the materials that have been produced are described in articles on Polybenzimidazoles, Polyether ether ketone, Polyimide adhesives and Polyphenylquinoxalines. Some of the general principles used in the search for enhanced thermal stability are discussed in this article. 

Further discussion on the general theme of high-temperature polymers and adhesives can be found in the articles entitled Polyphenylquinoxalines, Polybenzimidazoles and Polyether ether ketones. (See also article on High-temperature adhesives.)... 

Polyphenylquinoxalines S J SHAW Chemical constitution use as high-temperature adhesive... 

The results of a program to evaluate high-temperature adhesives for extended service have been reported by Hendricks et al" They used titanium lap shear coupons, prepared with either a polyphenylquinoxaline adhesive or a thermoplastic polyimide adhesive, to study the effects of thermal and humidity exposures. The polyphenylquinoxaline was affected by exposure... 

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