Hexamethoxymethyl melamine

Structural formula
General
Surname	Hexamethoxymethyl melamine
other names	HMMM; 2- N , 2- N , 4- N , 4- N , 6- N , 6- N -Hexakis (methoxymethyl) -1,3,5-triazine-2,4,6-triamine; Hexakis (methoxymethyl) melamine;
Molecular formula	C 15 H 30 N 6 O 6
Brief description	white solid
External identifiers / databases
EC number	221-422-3
ECHA InfoCard	100,019,475
PubChem	62479
Wikidata	Q27269977
properties
Molar mass	390.44 g mol −1
Physical state	firmly
density	1.2 g cm −3
Melting point	52 ° C
solubility	soluble in water
Refractive index	1,548
safety instructions
GHS labeling of hazardous substances	no GHS pictograms
	no GHS pictograms
H and P phrases	H: no H-phrases
	P: no P-phrases
Toxicological data	1050 mg kg −1 ( LD 50 , mouse , ipr ) ; 550 mg kg −1 ( LD 50 , rat , ipr ) ; > 17 g kg −1 ( LD 50 , rat , oral ) ;
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Hexamethoxymethylmelamine (HMMM) is a chemical compound from the group of melamine resins and is used for the formulation of paints . The name is derived from its molecular structure , the abbreviation of H exa m ethoxy m ethyl m elamin. Hexamethoxymethylmelamine is based on melamine , which contains three amino groups which are methylolated with formaldehyde and then etherified with methanol . HMMM belongs to the class of amino resins .

Extraction and presentation

Hexamethoxymethylmelamine is synthesized on the basis of melamine . A fully methylolated melamine is obtained by reaction with six equivalents of formaldehyde in a suitable solvent . This is a pure addition step. Further reaction with methanol produces HMMM with elimination of water. It is not necessary to separate the two conversion steps; for example, HMMM can be synthesized using excess methanol as the solvent. The synthesis takes place at slightly elevated temperatures of around 80 ° C.

Synthesis of hexamethoxymethylmelamine from melamine, formaldehyde and methanol.

Depending on how the reaction is carried out, oligomeric molecules are formed, which can sometimes have a major influence on the properties of the product obtained. Oligomeric molecules result from self-condensation of the methylolated melamine.

properties

HMMM resins have a broad solubility and are also water-soluble. This distinguishes HMMM from amino resins which are synthesized with high proportions of butanol or other non-polar residues as an etherifying agent. Due to their relatively low molar mass , HMMM resins have a very low viscosity and are therefore often used as co- binders in so-called high-solid paints. The HMMM resins used in the paint sector have a solids content of almost 100%, which in turn makes them ideal for use in high-solid paints, as hardly any solvents are introduced into the product.

At room temperature, HMMM is a solid. If the product contains small oligomeric proportions of HMMM as a result of the synthesis route, it is liquid. It is then no longer a pure and chemically uniform HMMM, but is often referred to as HMMM or HMMM resin.

use

Resins based on hexamethoxymethylmelamine are mostly used for paint formulations . Due to their broad solubility, HMMM resins can be used both in water-based paints and in conventional paint systems. Since it is a fully etherified melamine resin, a catalyst is used for crosslinking , as otherwise high temperatures would be required for the reaction. The low reactivity is also the reason why HMMM resins are rarely used in other areas.

When used in solvent-based paint systems, the low-viscosity properties mean that paint systems with a high processing solids content can be achieved.

safety

Like the physical properties, the safety-relevant data also depend heavily on the manufacturing process. The form of delivery (solvent content) and the amount of free formaldehyde , which is carcinogenic, are decisive for safety .

literature

Synthesis of etherified melamine resins: Patent WO002018115060A1

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g Entry on 2,4,6-Tris [bis (methoxymethyl) amino] -1,3,5-triazine at TCI Europe, accessed on September 4, 2018.
↑ ^a ^b ^c Entry on N, N, N ′, N ′, N ′ ′, N ′ ′ - Hexakis (methoxymethyl) -1,3,5-triazine-2,4,6-triamine in the ChemSpider database of Royal Society of Chemistry , accessed September 2, 2018.
↑ Krauß, Walter ,: Binder for solvent-based and solvent-free systems . 2., ext. and rework. Edition volume 2.1 . Hirzel, Stuttgart a. a. 1998, ISBN 3-7776-0886-6 , pp. 61 .
↑ Patent No. WO002018115060A1. Retrieved September 6, 2018 .
↑ Ulrich Poth: Synthetic binders for coating systems . Vincentz Network, Hannover 2016, ISBN 978-3-86630-611-0 , p. 161 .
↑ Roland Baumstark, Manfred Schwartz, Ulrich Poth, Reinhold Schwalm: Acrylate resins . Vincentz Network, Hannover 2014, ISBN 978-3-86630-820-6 , p. 75 .

[TCI-1] ↑ ^a ^b ^c ^d ^e ^f ^g Entry on 2,4,6-Tris [bis (methoxymethyl) amino] -1,3,5-triazine at TCI Europe, accessed on September 4, 2018.

[Chemspider-2] Entry on N, N, N ′, N ′, N ′ ′, N ′ ′ - Hexakis (methoxymethyl) -1,3,5-triazine-2,4,6-triamine in the ChemSpider database of Royal Society of Chemistry , accessed September 2, 2018.

[3] Krauß, Walter ,: Binder for solvent-based and solvent-free systems . 2., ext. and rework. Edition volume 2.1 . Hirzel, Stuttgart a. a. 1998, ISBN 3-7776-0886-6 , pp. 61 .

[4] Patent No. WO002018115060A1. Retrieved September 6, 2018 .

[5] Ulrich Poth: Synthetic binders for coating systems . Vincentz Network, Hannover 2016, ISBN 978-3-86630-611-0 , p. 161 .

[6] Roland Baumstark, Manfred Schwartz, Ulrich Poth, Reinhold Schwalm: Acrylate resins . Vincentz Network, Hannover 2014, ISBN 978-3-86630-820-6 , p. 75 .