water-based adhesive raw materials

Covestro Desmodur DN water-based solvent-free polyisocyanate

type	Low volatility aliphatic polyisocyanates
form of supply	Solvent-free yellowish medium viscosity liquid
use	Desmodur DN is a water-emulsifying, solvent-free polyisocyanate that can be used as a crosslinker for many medium pH polymer emulsions, such as polyurethane, polyvinyl acetate, acrylic and synthetic rubber emulsions. This crosslinking improves the adhesive's resistance to heat, water, plasticizers and solvents

technical parameter

characteristic	Numerical value	Units of measurement	method
NCO content	21.8±0.5	%	DIN EN ISO 11909，Annex A
Viscosity@23℃	1,250±300	mPa·s	DIN EN ISO 3219 A.3 Rotation

Other data*

characteristic	Numerical value	Units of measurement	method
solid content	about100	%
Density@20℃	about1.15	g/cm3	PIW 51757
Flash point	about180	℃	DIN51757

*This data is not used as a standard for the product.

application
To ensure that Desmodur DN can be fully dispersed in the adhesive, mechanical stirring should be used. Manual agitation is not necessary to form a homogeneous solution, especially when the viscosity of the adhesive dispersion is low, and adequate agitation is especially important. Insufficient stirring tends to form gel particles in the adhesive. After adding Desmodur DN, the two-component adhesive must be used up within its pot life. The length of pot life is not only related to the content of the polymer, but also to other ingredients (such as resins, thickeners, plasticizers, etc.). After the pot life (usually a few hours), the gel state is not always present. It can be reacted by measuring its heat resistance and water resistance. The addition amount of Desmodo DN is 3%-10% of 100 parts by weight of the adhesive dispersion (polymer content is 40%-60%).

Package
60kg metal container

storage
Store in the original sealed at 10-25°C, and can be stored stably for 6 months. This product is very sensitive to moisture and reacts with water to form carbon dioxide and insoluble urea. Therefore, the packaging container must be kept sealed at all times. Reactions with moisture, solvents and moisture in wet containers should be avoided. The carbon dioxide produced increases the pressure, making it more dangerous.

disposal
Residues should be incinerated according to local regulations. Uncrosslinked residues should be given special attention and marked with EWC No. 080406. The residue after crosslinking is designated as NO.080102.

Safety
Dangerous goods labels must not be removed until the contamination has been removed. Polyisocyanate products require special attention to the safety of their handling. High sensitivity tests in guinea pigs have shown that the product is prone to skin sensitization. However, the long-term experience of using aliphatic polyisocyanates and the test results under the conditions of use have shown that the risk of skin allergy should be small. The operating safety instructions for this product should be followed. Its content involves marking, transportation, storage, handling, product safety and ecology.