Determination of total amine or equivalent weight

Ethoxylated amines with short ethylene oxide chains can be titrated with sodium dodecyl sulphate and NaTPB in acid solution, but the titrations become increasingly unsatisfactory as the chain length increases. The same is no doubt true of ethoxylated diamines. Commercial ethoxylated amines have typically 12-60 EO units, and the diamines have up to 25. 

The recommended method is the indicator method for total amine given in section 7.2.1. Use a sample of 4-5 meq, dissolved in 150 ml propan-2-ol. The procedure is as described. The method used by Akzo [27] uses rather small sample weights and obtains rather small titrations this is a scaled-up adaptation. 

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