Application of isophorone in polyurethane

Isophorone is an important high-boiling point solvent. In addition to being used as a solvent, it is also used in the production of polyurethane, coatings, and medicines. , elastomers, special cellulose, food and adhesives, and other fields. From the late 1980s to the early 1990s, it developed rapidly abroad and was widely used in the United States, Japan, Western Europe and other countries and regions. The main foreign manufacturers of isophorone are: American Romhas Company, Dow Chemical Company, British BP Company, German Verba Company, and Japanese Daizo Company. There is currently no formal manufacturer in my country, and only the Shanghai Solvent Factory produces it on a small scale.

Isophorone is one of the derivatives of acetone. It is obtained from acetone through an alcohol anhydride condensation reaction in the presence of an alkaline catalyst and water, followed by dehydration, cyclization and deketonesis. There are two main methods for synthesizing isophorone from acetone. One is the pressurized liquid phase condensation method in an alkaline solution; the other is the heterogeneous catalytic condensation method using a solid catalyst, which is mostly used in foreign industrial production of isophorone. Liquid phase compression is legal, and the process is mature. However, the reactor is a high-pressure equipment with complex internal structure and high cost. The waste liquid contains a large amount of potassium hydroxide, the reactive distillation operation is difficult to control, and the acetone conversion rate is not high. In recent years, the research direction has been gas-solid multi-phase catalytic condensation method, and there have been many patent reports abroad.

Because isophorone has a high boiling point, low hygroscopicity, and tiny evaporation rate, thus becoming important in ketone solvents. This product has strong dissolving ability, good dispersion and leveling properties. It is a good solvent for polymer materials and can dissolve nitrocellulose, acrylic resin, alkyd resin, polyester, epoxy resin, etc. Isophorone has a wide range of uses. In addition to being used as a solvent, it also has many applications in polyurethane: for example, isophorone diisocyanate (IPDI) is produced by addition, hydrogenation and phosgenation of isophorone.