Mdi-50 Performance Research And Applications

MDI is a very important raw material in polyurethane industry, and 2,4'-MDI is one of the production in MDI's manufacture. For a long time, 2,4'-MDI had not been used largely, because of people's cognizing limits and shortage of application studies. On the other hand, because it cost too much to completely seprate 2,4'-MDI, so all of the production in the market is the admixture of 2,4'-MDI and 4,4'-MDI, its inland trademark is MDI-50.In this study, first of all, through mixing MDI-100 with high 2,4'-MDI content MDI we gained MDI-50 that it's 2,4'-MDI content was required. Then we studied MDI-50's physical, chemical property and MDI-50 prepolymer's stock stability. At last, we applied MDI-50 to encapsulants for electronics and athletic tracks, and gained satisfactory result.The property of MDI-50 is the property of 2,4'-MDI, the aim of this article is to find the application area suitable for MDI-50. By the comparison of the property of MDI-50, MDI-100 and TDI-100, we can concluded how to use MDI-50 in some area.Though MDI-50 can be stored in normal temperature, its not very steady. Prepolymer is the most directly and most efficient application manner of MDI-50, and its most important property is viscosity and stock stability. Through varying reacting conditions, such as 2,4'-MDI content, polyether species and NCO content, we find the factor influencing the property of MDI-50 prepolymer, and gained stock stable prepolymer.Synthesis of encapsulants for electronics is simple, its reaction is noumenal. In the article, good reacting conditions were investigated and good encapsulants were obtained through using MDI-50. From the reaction process, we can also testify the property of MDI-5 0 which different from MDI-100 and TDI." Prepolymer based on MDI-50 for athletic tracks was prepared, the effects of catalyst, rubber granule and DOP on reacting and product performance were also studied. Property of MDI-50 based athletic tracks can achieve the level of GB Standard and its strength property enormously exceed the index of the Standard. Wealso succeeded in the practice.From above researches ,we concluded that in some area MDI-50 can be used as a substitute for MDI-100 and TDI, it is important in the usage of MDI-50.The article consists of the following sections:1 Summary of the development about MDI-502. Preparation and confirm of MDI-503 Study on the basic property of MDI-504 Prepatation of MDI-50 based prepolymer and study on its property5 Application study of MDI-50 in encapsulants for electronics and athletic tracks...