DESMODUR BL 3175 SN

Synonyms:
Hexamethylene-1,6-diisocyanate;  1,6-diisocyanatohexane; aliphatic polyisocyanate; DESMODUR BL 3175 SN; DESMODUR; DESMODUR BL3175SN; DESMODUR-BL-3175-SN; Desmodur BL 3175 sn; Desmodür bl 3175 sn; Hexa methylene-1,6-diisocyanate;  1,6-di isocyanatohexane;  Hexa methylene-1,6-di iso cyanate;  1,6-diiso cyanatohexane; DESMODUR BL; DESMODUR BL 3175

DESMODUR BL 3175 SN
DESMODUR BL 4265 SN
Technical Datasheet 
DESMODUR BL 4265 SN is a blocked, aliphatic polyisocyanate based on IPDI. Can be thinned to a solids content of 40 % with ketones, esters, ether esters, aromatic hydrocarbons and solvent naphtha® 100, 150 and 200. It has only limited thinnability with aliphatic hydrocarbons. Shelf life of DESMODUR BL 4265 SN is 6 months.
Product Type    Polyurethanes > PU-Prepolymers > Isocyanates > IPDI-based
Chemical Composition    Aliphatic polyisocyanate based on IPDI
Physical Form    Liquid

Desmodur BL 3175 SN

In combination with Desmophen grades to formulate lightfast, one-component polyurethane stoving coatings; as an additive in conventional stoving systems to improve flexibility and adhesion.
Form supplied approx. 75 % in solvent naphtha®100
Specification
Property Value Unit of measurement Method
Non-volatile content
(0.2 g / 60 min / 80 °C)
75 ± 2 % M020-ISO 3251
Viscosity at 23 °C 3,300 ± 400 mPa·s M014-ISO 3219/A.3
Color value (Hazen) ≤ 60 M017-EN 1557
Free NCO content, modified ≤ 0.2 % M105-ISO 11909
Other data*
Property Value Unit of measurement Method
Blocked NCO content approx. 11.1 %
Viscosity at 25 °C approx. 2,800 mPa·s M014-ISO 3219/A.3
Equivalent weight approx. 380
Flash point approx. 45 °C DIN 53 213/1
Density at 20 °C approx. 1.06 g/ml DIN EN ISO 2811

Solubility / thinnability Generally speaking, Desmodur
 BL 3175 SN has good compatibility with the
solvents listed. However, the solutions formed must be tested for their storage
stability. Desmodur BL 3175 SN can be thinned to a solids content of 40 % by wt. with ketones, esters, ether esters and aromatics. It can be thinned to a solids content of 60 % by wt. with mixtures of higher boiling aromatics such as solvent naphtha® 100 and 150. Aliphatic hydrocarbons cannot be used.
Compatibility Given equivalent crosslinking (NCO/OH = 1.0), Desmodur BL 3175 SN is generally compatible with Desmophen 651, 670, 680, 690, RD 181, A 160, various polyacrylates and with Desmophen®T 1665. It can also be combined with various plasticisers, e.g. phosphoric acid, sulphonic acid, adipic acid and phthalic acid esters. The combinations should always be tested for their compatibility.

Properties / Applications Desmodur BL 3175 SN can be used as the hardener in colorfast and weather-stable, one-component polyurethane coatings. The stoving temperature can be significantly reduced by the addition of a catalyst, e.g. dibutyltin dilaurate (DBTL), without reducing the storage stability.The product is used in high-grade industrial finishes (electrical appliances, small components, can coatings, coil coatings, etc.) and in primer surfacers and topcoats for automative finishing. Desmodur BL 3175 SN can also be used as an additive in conventional stoving systems to improve the flexibility and adhesion. Possible stoving cycles for Desmodur BL 3175 SN combined with Desmophen 651 are:
without catalyst
160 °C 60 min
or180 °C 15 min
or200 °C 7 min
with catalyst
130 °C 60 min
or150 °C 15 min
or175 °C 7 min
Depending on the co-reactant used and the stoving time, yellowing may occur at temperatures above 160 °C. Used in coil coating systems, Desmodur BL 3175 SN crosslinks sufficiently without the addition of DBTL from a peak metal
temperature of approx. 241 °C and above. With an addition of 1 % DBTL, calculated on solid resin, the same result is achieved from approx. 224 °C peak metal temperature.

Storage - Storage in original sealed  container.
- Recommended storage temperature: 0 - 30 °C.
- Protect from moisture, heat and foreign material.
General information: Storage at higher temperatures will result in increase of color and viscosity. Storage at significant lower temperatures will result in solidification. This solidification is reversible by briefly heating the product without adversely affecting the quality of the product.

Blocked aliphatic HDI-polyisocyanate. With Desmophen grades to formulate lightfast one-component polyurethane stoving coatings; as an additive to improve flexibility and adhesion.

Product Types
PIC
Crosslinkers
Hardeners
Aliphatic polyisocyanate
Isocyanate
Polyisocyanurate
Polyisocyanate
Material
Coatings
Elastic, Thermally resistant, Solventborne, Flexible
General Characterization
Blocked, aliphatic polyisocyanate based on HDI.
In combination with Desmophen® grades to formulate lightfast, one-component polyurethane stoving coatings; as an additive in conventional stoving systems to improve flexibility and adhesion.
Color value (Hazen)    M017-EN 1557        ≤ 60
Non-volatile content (0.2 g / 60 min / 80 °C)    M020-ISO 3251    %    75 ± 2
Free NCO content, modified    M105-ISO 11909    %    ≤ 0.2
Viscosity at 23 °C    M014-ISO 3219/A.3    mPa*s    3,300 ± 400 

Aliphatic polyisocyanate based on HDI. Used in combination with Desmophen grades to formulate lightfast, one-component polyurethane stoving coatings. Also suitable for use as a hardener to formulate lightfast one-pack stoving polyurethane coatings to improve flexibility and adhesion. Designed for high grade industrial finishes including electrical appliances, small components, can coatings and coil coatings, primer surfacers and top coats for automotive finishing.

Isocyanate is the functional group with the formula R−N=C=O. Organic compounds that contain an isocyanate group are referred to as isocyanates. An organic compound with two isocyanate groups is known as a diisocyanate. Diisocyanates are manufactured for the production of polyurethanes, a class of polymers.[1]

Isocyanates should not be confused with cyanate esters and isocyanides, very different families of compounds. The cyanate (cyanate ester) functional group (R−O−C≡N) is arranged differently from the isocyanate group (R−N=C=O). Isocyanides have the connectivity R−N≡C, lacking the oxygen of the cyanate groups.

Production
Isocyanates are produced from amines by phosgenation, i.e. treating with phosgene:

RNH2 + COCl2 → RNCO + 2 HCl
These reactions proceed via the intermediacy of a carbamoyl chloride (RNHC(O)Cl). Owing to the hazardous nature of phosgene, the production of isocyanates requires special precautions

Common applications
MDI is commonly used in the manufacture of rigid foams and surface coating.[1] Polyurethane foam boards are used in construction for insulation. TDI is commonly used in applications where flexible foams are used, such as furniture and bedding. Both MDI and TDI are used in the making of adhesives and sealants due to weather-resistant properties. Isocyanates, both MDI and TDI are widely used in as spraying applications of insulation due to the speed and flexibility of applications. Foams can be sprayed into structures and harden in place or retain some flexibility as required by the application.[10] HDI is commonly utilized in high-performance surface-coating applications, including automotive paints.