Polyhydantoins

Figure 21.12. Dependence of temperature (at 50Hz) and frequency (at 23°C) on the dielectric constant and power factor of polyhydantoin film...

Closely related to the polyhydantoins are the 2,4,5-triketoimidazolidine polymers, known as polyfparabanic acids) and produced by Exxon (Tradlon) and Hoechst. They contain the basic structure... 

A considerable number of non-cross-linked aromatic and heterocyclic polymers has been produced. These include polyaromatic ketones, aromatic and heterocyclic polyanhydrides, polythiazoles, polypyrazoles, polytriazoles, poly-quinoxalines, polyketoquinolines, polybenzimidazoles, polyhydantoins, and polyimides. Of these the last two have achieved some technical significance, and have already been considered in Chapters 21 and 18 respectively. The most important polyimides are obtained by reacting pyromellitic dianhydride with an aromatic diamine to give a product of general structure (Figure 29.17). 

COMPIMIDE 796-COMPIMIDE 123. b Resisttherm PH-10 polyhydantoin. c Resistofol N polyhydantoin. d Matrimide 5218 polyimide. 

A mixture of a BMI (Compimide 796) with 4,4 -bis(orf/zo-propenylphe-noxy)benzophenone (TM 23) was blended in solution with Udel 700 (polysul-fone from Union Carbide), Ultem 100 (General Electric polyether imide), and PH 10 (Bayer polyhydantoin) (Fig. 35). The thermoplastics were introduced at various concentrations up to 33%. A phase segregation did not appear with PH 10, but two phases were observed with Ultem. With both semi-IPNs the observed Glc were found to be four- to fivefold the Glc of the neat BMI [113]. 

A coating composition consists of BPA/DC-BMI prepolymer, epoxide resin and Zn acetate in dimethylformamide a solution of polyhydantoin in CH2C12 is added [121]. 

Observed Tg s vary from -123°C for polyfdimelhyl siloxane) (1-43) to 273°C for polyhydantoin (11-2) polymers used as wire enamels and to even higher temperatures for other polymers in which the main chain consists largely of aromatic structures. This range of behavior can be rationalized, and the effects of polymer structure on Tg can be predicted qualitatively. Since the glass-to-rubber transition... 

Uses For polyurethane industry for adhesives, binders, coatings, and sealants, molded elastomers, stmcturalfoam molding, appliances prod, of polyhydantoin resins, urethane-acrylate resins Trade Names Papi901... 

Stenzenberger, in his papers [1,29] for toughening bismaleimide resins, cites the use of thermoplastics such as polyhydantoins [55] (Bayer s Resistofol N, Resistherm PH-10),... 

Interestingly, this kind of polymer serves as a valuable precursor for conversion into the corresponding polyhydantoin [65]. Simple basic treatment with potassium hydroxide afforded the polyhydantoin after 48 h. Thus, this protocol demonstrates the first non-isocyanate-based approach for the synthesis of polyhydantoins. 

Sehlinger A, Schneider R, Meier MAR (2014) Ugi reactions with C02 access to functionalized polyurethanes, polycarbonates, polyamides, and polyhydantoins. Macromol Rapid Commun 35(21) 1866-1871... 

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