The applications of dichloromethane in the polyurethane industry mainly include the following aspects:
As a solvent and reaction medium: In the production process of polyurethane, dichloromethane can be used as a solvent to help dissolve polymers and promote reactions. At the same time, it can also be used as a reaction medium to participate in the synthesis reaction of polyurethane to improve the degree of polymerization and heat resistance.
Physical foaming agent: Dichloromethane is a commonly used physical foaming agent, especially in polyurethane polyether soft foam, it regulates the reaction heat by gasification and heat absorption, affecting the physical properties of the foam. Increasing the amount of dichloromethane can increase the elongation of the foam, but may reduce its tear strength. In addition, the increase in dichloromethane will reduce the internal temperature rise during the reaction, affect the generation of hard segments, and make the foam softer and more elastic.
Regulating reaction heat: Dichloromethane regulates the heat change in the polyurethane reaction process by gasification and heat absorption. Its heat of vaporization is 29KJ/mol, which can effectively absorb the reaction heat, affecting the release rate of the reaction heat and the physical properties of the foam.
Safety Issue: Dichloromethane is a toxic and hazardous chemical. Professional training and strict compliance with regulations are required when using it. You should fully understand its properties before use, take personal protective measures, and stay away from fire, high temperature, static electricity and other substances that may cause danger.