Polyurethane foaming catalyst is a substance that can accelerate the foaming of polyurethane resin. They are used in a variety of applications including the production of flexible, rigid and specialty foams.

There are many types of polyurethane blowing catalysts, each with its own advantages and disadvantages. Some of the most common types of polyurethane blowing catalysts include:

Amines: Amines are the most common polyurethane blowing catalysts. They effectively catalyze the reaction between isocyanate and water to produce carbon dioxide gas, which creates foam. However, amines also lead to the formation of undesired by-products, such as amines and amides.
Organotin compounds: Organotin compounds can also effectively catalyze the reaction of isocyanate and water to generate carbon dioxide gas. However, they are more expensive and difficult to handle than amines.
Metal salts: Metal salts, such as zinc chloride, can also be used as polyurethane foaming catalysts. They are less expensive than amines and organotin compounds, but not as effective at catalyzing the reaction of isocyanates and water to form carbon dioxide.
The choice of polyurethane blowing catalyst depends on a variety of factors, including the type of polyurethane resin used, the properties desired in the final product, and the cost of the catalyst.

Polyurethane blowing catalysts are an important part of the polyurethane manufacturing process. They help ensure that polyurethane resins are properly foamed and that the final product has the desired properties.