Polyurethane catalysts are generally classified into: tertiary amine catalysts and organometallic catalysts. Subdivision can be further divided into tertiary amine catalysts, alcohol amine catalysts, ammonium salt catalysts, common organometallic catalysts, and organic precious metal catalysts.
I. Polyurethane foam industry
The polyurethane foam industry has a heavy reliance on polyurethane catalysts. It is essential that the viscous polyols and isocyanates be converted into solid porous materials by mixing and stirring. The catalyst is indispensable.
Polyurethane foam industry requires more catalysts, that is, there must be foaming catalysts, but also need to have chemical debonding chemical catalysts, balanced catalysts, some products need to be delayed (DY-215/DY-225/DY-8154, etc. ), Triple effect. Since it is difficult to use a single catalyst to achieve an ideal gel and foaming balance, it is common to use a plurality of catalysts together.
Commonly used catalysts are: DY-1, DY-33, DY-9, DY-DMEA and so on.
Second, polyurethane coatings, adhesives industry
The demand for catalysts in the coatings and adhesives industry is roughly in two aspects: 1. The synthesis of prepolymers. 2. The product is cured. The most widely used catalysts in these two industries are organic metals such as DY-9 and DY-12; some systems also use amine catalysts such as DY-DMEA and DY-DMDEE. However, with the development of the EU's latest environmental protection standards in 2012, the application of butyl tin products has been greatly limited, and therefore the chemical requirements for organic germanium (DY-20), environmental tin (DY-28), and organic amine catalysts have greatly increased. At the same time, due to the requirements of the construction process, catalysts such as DY-5503/DY-5508/DY-5982, which can provide high-quality fluidity in the early stage, are becoming more and more popular in the industry.
Third, polyurethane elastomer industry
Most of the elastomers require almost no moisture in the system, because the introduction of water will cause the formation of bubbles in the elastomer system, which will affect the quality of the product. This part of the elastomer almost completely excludes the tertiary amine catalysts. In addition, many organic chemicals such as organomercury are selected by Desheng Chemical. However, the toxicity, price, and difficulty of purchasing organic mercury are issues that cannot be ignored by practitioners.
Polyurethane synthetic leather resins also belong to the category of elastomers. Their use of Dexy chemical catalysts is prominent in the synthesis process of resins. The requirements for air bubbles in the system are not very demanding. Almost all resin plants are using high recovery of water. DMF confirms this. However, in the production of wet processing materials, we prefer to create a microcellular foam structure during the pimesis treatment. However, this industry is heavily dependent on foreign markets, and organic tin catalysts have been replaced without delay.
In the polyurethane elastomer industry, there is also a major category, namely, microcellular elastomers, which represent the industry: shoe soles. Due to the need of its chemical products, Dextron Chemicals generally chooses tertiary amine catalysts. At the same time, it has certain requirements on the chemical properties and environmental protection of the mobile audio chemicals, so the ammonium catalysts have a large space for use.