Hexamethylenediamine
Structural formula | ||||||||||||||||||||||
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General | ||||||||||||||||||||||
Surname | Hexamethylenediamine | |||||||||||||||||||||
other names |
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Molecular formula | C 6 H 16 N 2 | |||||||||||||||||||||
Brief description |
hygroscopic, silky glossy leaves with an ammonia-like odor |
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properties | ||||||||||||||||||||||
Molar mass | 116.21 g mol −1 | |||||||||||||||||||||
Physical state |
firmly |
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density |
0.89 g cm −3 |
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Melting point |
41 ° C |
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boiling point |
204 ° C |
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Vapor pressure |
34.4 Pa (100 ° C) |
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solubility |
Easily soluble in water (800 g · l −1 at 20 ° C) and ethanol |
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safety instructions | ||||||||||||||||||||||
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Toxicological data | ||||||||||||||||||||||
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Hexamethylene diamine (HMD, HMDA) is a chemical compound from the group of aliphatic amines and an important precursor for the manufacture of polyamides .
Manufacturing
Hexamethylenediamine is produced on an industrial scale by hydrogenating adiponitrile using two different processes. In the first process, which was developed by DuPont , the hydrogenation takes place in the presence of ammonia at a high pressure of around 250 bar. The catalyst is a fixed bed made of iron. In the second process, which was developed by the company Rhodiatoce (a joint venture between Rhône-Poulenc and Montecatini ), hydrogenation is carried out at an average pressure of around 40 bar. The hydrogenation takes place without a solvent with small added amounts of alkali metal hydroxides (e.g. sodium hydroxide ) over Raney nickel catalysts in suspension.
In the laboratory, production from furfural is recommended , in which furfural is decarbonylated via a ZnO - Cr 2 O 3 contact . With the furan obtained , an ether cleavage (favored by the diene character) can now be carried out with HCl . After reaction with sodium cyanide and complete hydrogenation , hexamethylenediamine is also obtained.
use
Hexamethylenediamine is an intermediate for polyamides such as nylon . This plastic ( polymer ) is formed as a condensation product from adipic acid and hexamethylenediamine with elimination of water, the monomeric intermediate stage is also called AH salt after the initial letters of the components . By the reaction of hexamethylene diamine with phosgene is hexamethylene diisocyanate which as component for the production of obtained polyurethanes is used.
Through systemic studies on the reaction of lactose / lactulose with amines , it was discovered in January 2019 that hexamethylenediamine in a strongly alkaline solution (pH 13) produces a similar red color as the Wöhlk reaction and Fearon's test . The reaction with 0.025 molar hexamethylenediamine solution at 60 ° C performs significantly better in the risk assessment than the comparable processes with ammonia and methylamine. It can be used to detect 1,4-linked disaccharides (lactose, maltose , cellobiose ). The cherry-red dye has an absorption maximum at 550 nm.
Individual evidence
- ↑ Entry on 1,6-HEXANEDIAMINE in the CosIng database of the EU Commission, accessed on February 12, 2020.
- ↑ a b c Entry on hexane-1,6-diamine. In: Römpp Online . Georg Thieme Verlag, accessed on December 25, 2014.
- ↑ a b c d e f g h Entry on hexamethylenediamine in the GESTIS substance database of the IFA , accessed on February 1, 2016(JavaScript required) .
- ↑ Entry on Hexamethylenediamine in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
- ↑ Klaus Ruppersberg, Horst Klemeyer: Lactose rapid test: How can you detect milk sugar in 60 seconds? In: CHEMKON . Wiley-Verlag, January 23, 2020, ISSN 0944-5846 , doi : 10.1002 / ckon.201900064 .