Chemical Properties
Lupranate® MI is a pure MDI product, but contains a higher proportion of the 2,4' isomer than LUPRANATE® MS. The higher 2,4'-iso conformation makes MI products at room temperature. Liquid and relatively low reactivity. From a chemical structure perspective, the 2,4' isomer is more flexible than the 4,4' isomer, and its functionality is 2.0.
Application
Lupranate® MI provides isocyanate groups in the production of flexible, semi-flexible and microcellular polyurethane foams for the production of adhesives and sealants.
Basic performance
Project |
Unit |
Value |
Appearance |
— |
Colorless to slightly yellow liquid |
Purity |
wt.% |
> 99.5 |
NCOContent |
wt.% |
33.5 |
4,4'-Isomers |
wt.% |
45 - 51 |
EHC |
ppm |
<150 |
25Density at ℃ |
g/cm3 |
1.22 |
Shipping
Lupranate® MI can be supplied in tank trucks or non-recyclable steel drums, with a barrel capacity of 250kg. If transported by road tanker, the temperature should be controlled between 23°C and 30°C, and the temperature of barrel transportation should not be lower than the freezing point. Exposure to strong light should be avoided.
Save
Lupranate® MI should be protected from moisture, oxygen and ultraviolet light to cause discoloration, but discoloration does not affect product application. The ideal storage temperature is between 23°C and 30°C. Under this temperature condition, avoiding moisture and oxygen, Lupranate® MI can be stored for at least 3 months. Barrels must be airtight and storage tanks must be nitrogen sealed. If left for too long, dimers will be formed to produce suspended solids and precipitation. When the temperature is lower than 15-20°C, the 4,4' isomer will crystallize out and must be heated and melted immediately. The heating time should be as short as possible. The solid can be melted by heating at 80°C for 8 to 12 hours, but its precipitation temperature is different. If the heating time is too long or too high, the melted Lupranate® MI may be turbid due to the formation of unmeltable polymer. Also note that heating and stirring must be uniform because the crystallization temperatures of the 2,4' isomer and the 4,4' isomer are different.
Storage at high temperatures may cause discoloration or formation of solids, which will not melt when heated.