Evonik Degussa VESTAMIN A95 sodium sulfamate aqueous solution chain extender
Product introduction
VESTAMIN A95 is an aqueous solution of sodium sulfamate with a solid content of about 50%. The first and second amino groups combine the properties of emulsifiers and chain extenders in the process of synthesizing polyurethane aqueous dispersions. At room temperature, VESTAMIN A95 has a low viscosity, a clear, transparent, slightly yellow liquid with a slight amine odor.
Features
|
performance |
Determination standard |
unit |
Numerical value |
|
solid content |
DIN EN ISO3251（1h/120℃） |
%weight |
51±2 |
|
Amine value |
DIN 53 176 mod |
mg KOH/g |
250±20 |
Typical data
|
equivalent |
约220 |
-- |
-- |
|
Density@20℃ |
1.225 |
g/cm3 |
DIN EN ISO 2811-2 |
|
Viscosity@20℃ |
< 20 |
mPa·s |
DIN EN ISO 3219 |
|
Color (Gardner) |
< 2 |
-- |
DIN EN ISO 4630 |
|
Vapor pressure@20℃ |
23 |
hPa |
|
|
Flash point |
>100 |
℃ |
DIN EN ISO 2719 |
|
PH value (20g/L water@20℃) |
11-12 |
-- |
DIN ISO 976 |
|
set temperature |
< -10 |
℃ |
DGF-C-IV-3A |
performance and application
Due to its chemical structure, the fatty amine VESTAMIN A95 can be used as a chain extender for the production of polyurethane dispersions, while sodium sulfonate acts as an anionic emulsifier. VESTAMIN A95 is often recommended for use in the acetone process.
Polyurethane dispersions synthesized with VESTAMIN A95 have better stability than flocculation under non-alkaline conditions and therefore better compatibility with other anionic or nonionic dispersions. The hydrolytic stability of polyesters in aqueous polyurethane dispersions is improved due to the lower ammonia number.
There are two ways to use VESTAMIN A95:
NMP method: Add VESTAMIN A95 to the prepolymer at 40°C, the temperature will rise to about 60°C due to the exothermic reaction, and stir for about 5 minutes before dispersion.
Acetone method: Add VESTAMIN A95 to the prepolymer solution at a moderate temperature, quickly heat to 50°C before dispersing, and remove acetone by distillation.
VESTAMIN A95 must be synthesized in one step in order to prevent the isocyanate functional group of the prepolymer from reacting with water.
storage and packaging
VESTAMIN A95 is available in 200kg and 30kg non-recyclable plastic drums. VESTAMIN A95 is stable for at least 1 year when stored as directed in an airtight container.
