BQ7290 is a TDI prepolymer modified with specialty polyurethane polyol.
At room temperature it is a colorless to light-yellow liquid.
BQ7290 is mainly used for solvent-free, corrosion-resistant rubber rollers.
By adjusting the curing-agent ratio, the final hardness can be tailored from Shore 55 A to Shore 92 A.
Appearance: Light-yellow liquid
Viscosity @ 25 °C: 1 500 – 2 100 mPB·s
NCO content: 3.9 – 4.5 %
Density @ 25 °C: 1.05 – 1.10 g/cm³
Packaging
210 L steel drum, 200 kg net
20 L steel pail, 20 kg net
Storage & Handling Precautions
Because of its highly reactive nature, SDNB-7290 readily reacts with moisture to form insoluble ureas and release CO₂, causing drum bulging and viscosity rise. Containers must therefore be kept absolutely dry, tightly sealed and blanketed with dry nitrogen.
Store at 15 – 25 °C in a well-ventilated room. If the storage temperature falls below 10 °C, crystallization may occur. In such cases, warm the drum promptly and evenly in a 70 – 80 °C hot-air oven equipped with a drum-rolling device. Local overheating must be avoided; decomposition begins above 230 °C and generates gases. After melting, homogenize the contents thoroughly.
Prolonged storage above 50 °C will produce insoluble solids and increase viscosity. Under the recommended storage conditions the shelf life is 9 months from the date of manufacture. Product that has exceeded its stated shelf life but still meets the specification range can generally still be used.
Shelf Life
9 months from the production date when stored under the above conditions.