Toluenediamine isomers

Although all six possible toluenediamine isomers are made in the commercial synthesis, only two products are available commercially. The properties of the individual isomers are summarized in Table 1. Specifications for the commercial products, named by the relative position of the predominant groups, along with some physical properties, are shown in Table 2. 

Synonyms/Trade Names Diaminotoluene, Methylphenylene diamine, TDA, Toluenediamine isomers. Tolylenediamine [Note Various isomers of TDA exist] ... 

Toluenediamine is classed as toxic. The oral LD q for animals is between 270—350 mg /kg body weight (45). TDA is readily absorbed through the skin and this is the major route of human exposure. Several studies have shown the 2,4 isomer of TDA to be carcinogenic for rats and mice, but tests on the 2,5 and 2,6 isomers were not positive. AH three of the isomers have been shown to be mutagenic (45). Results of limited studies on the reproductive ha2ards for male workers are equivocal, but animal experiments have shown TDA to cause adverse reproductive effects (45). 

Until the mid-1960s, phenylenediamines were used primarily for oxidative purposes the para isomer was of major importance. Since then, the use of phenylenediamines to manufacture polymers has far exceeded their use for oxidative purposes. The y -phenylenediamines, (2,4 and 2,6)-toluenediamine, are widely used for the manufacture of polyurethanes. Phenylenediamines are dihinctional and react with other dihinctional compounds, such as dianhydrides, diacyl chlorides, dicarboxyHc acids, and disulfonyl chlorides to give polyamides. Phenylenediamines also give polymers with epoxides, diols, diacetals. 

Benzenediamine, ar-methyl- Diaminotoluene Diamino-toluene (mixed isomers) EINECS 246-910-3 HSDB 6059 Methylphenylenediamine Phenylenediamine, ar-methyl- RCRA waste number U221 TDA 8020 Toluene-ar,ar -diamine Toluenediamine Tolylenediamine. 

The largest volumes of phenjienediamines are used for the production of polymers, primarily polyurethanes, where the diisocyanates of toluenediamines (meta isomer) are used. For the manufacture of polyamides both meta and para isomers are used. Another significant use for -phenylenediamines is as antioxidants and antiozonants for elastomers, plastics, and petroleum products. The /V-alkyl-/V-aryl- -phenylenediamines are by far the most commonly used and represent the bulk of the volume of the iV-substituted -phenylenediamines reported in Table 3. Some iV iV-dialkyl compounds ate also stiU used as antiozonants, but they oxidize more rapidly and lose activity sooner. The iV,iV-diaryl-/)-phenylenediamines ate used primarily as antioxidants, especially where copper and other harmful metals might be present. -Dinaphthalenyl- -phenylenediamine is especially effective in this application. The... 

---