Meta-phenylenediamine

Polyether Imides. Polyether imides (PEIs) are amorphous, high performance thermoplastic polymers that have been in use since 1982. The first commercial polyether imides were the Ultem series developed by the General Electric Co. The first, Ultem 1000 [61128-24-3] is prepared from phthahc anhydride, bisphenol A, and meta-phenylenediamine and has the following stmcture ... 

Meta-phenylenediamine, a crystalline solid with a melting point of about 60°C, gives cured resins with a heat distortion temperature of 150°C and very good chemical resistance. It has a pot life of six hours for a 200 g batch at room temperature whilst complete cures require cure times of four to six hours at 150°C. About 14 pts phr are used with the liquid epoxies. The main disadvantages are the need to heat the components in order to mix them, the irritating nature of the amine and persistent yellow staining that can occur on skin and clothing. The hardener finds use in the manufacture of chemical-resistant laminates. 

PI-2545, and from 3,31,4,41-benzophenone tetracarboxylic dianhydride (BTDA) and ODA, PI-2555. Meta-phenylenediamine (MPD) is also present in PI-2555 as a minor component Q). Its presence has a negligible affect on the results of this study, other than a possible broadening of the spectral band ascribed to the rotation of the imide-phenyl bond, and hence will not be discussed further. 

Oxidation dye couplers are electron-rich aromatic species. They are commonly substituted resorcinols or meta-phenylenediamines, usually containing a vacant position para to the amine or phenolic group (see Table 6-2). Oxidation dye precursors, when oxidized in the absence of couplers, form colored compounds, usually gray or brown-black shades. On the other hand, couplers themselves usually produce little or no color, but in the presence of precursors and oxidizing agent, they modify the color formed by the precursor. 

Footnote A Dr G. Spica (Rivista, Aug. 1897) proposes to use hydrochloride of meta-phenylenediamine.] -Exudation and Liquefaction Test for Blasting Gelatine, Gelatine Dynamite, c.—A cylinder of blasting... 

Treatment of the dianhydrides with various diamines finally gives polyetherimides in very high yields. Again, we could list a very large number of polyetherimides prepared via imidization polymerization. Suffice it to say the most important one at the moment is that derived from bis-phenol-A, 4-nitro phthalimide, and meta-phenylenediamine. It s glass transition temperature is 218°C. 

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