Baytec® SPR-092A

Isocyanate Component — The isocyanate component (MDI prepolymer) must be stored in tightly closed containers and protected from contamination with moisture and other foreign substances, which can adversely affect processing. It will react slowly with water to form ureas and carbon dioxide gas, which may cause sealed containers to expand and rupture. Partially filled containers should be blanketed with dry nitrogen. Storage temperatures should be maintained betweeen 15°C and 35°C (59°F and 95°F). Under these conditions, the shelf life of this isocyanate component is six months after receipt of product by customer. Within this range, a storage temperature of 25°C (77°F) will maximize the storage life of the product. The isocyanate component must not be allowed to freeze. Exposure to temperatures less than 15°C (59°F), even for short periods of time, can result in the formation of solid material. During the winter months, appropriate precautions must be taken during shipment and storage.
Prolonged storage of the solid or partially solid isocyanate component may result in the formation of MDI dimer in amounts which exceed its solubility in the prepolymer at normal storage temperatures. This can make the product unusable.
If solids should form because of exposure of the isocyanate component to lower temperatures, it may be possible to re-liquify the prepolymer by reheating. Use a well-ventilated oven for the minimum time necessary to render it clear. The temperature of the prepolymer should not exceed 60°C (140°F). Agitation or drum rollers are recommended to avoid excessive local heating, which will degrade the prepolymer. Significant amounts of MDI dimer may form during the heating process. As a result, the remelted prepolymer may be cloudy, and the processing behavior and properties of the final product may be affected.
Polyol Component — The polyol component is hygroscopic ... text to long! (max 2000 characters)