Polyurethane is one of the most versatile polymers. It is used as an insulation, coating, adhesive and rigid plastic material. Polyurethane can be produced in different forms: flexible and cross-linked foam, elastomer or as a coating.
MDI/TDI Polyurethanes are produced by reacting an isocyanate, usually TDI (toluene diisocyanate) or MDI (methylene diphenyl diisocyanate), with a polyol (eg ethylene or propylene glycol). Depending on the expected end product, additives or other ingredients are added to obtain the desired formulation.
During the production process, raw materials are pumped from their holding tank to a pressure reactor, where they are heated and stirred, controlling pressure and temperature.
"Pure" MDI or TDI is produced by the reaction of a diamine (MDA or TDA) with phosgene. The crude diisocyanates are then fractionated in a distillation column to produce purer mixtures of isomers. At the bottom of the column, a mixture of MDI or TDI and tar is sent through an evaporation and drying process for recovery to increase the yield of the MDI/TDI unit.
Viscosity is a crucial parameter for the evaporation of MDI/TDI and can also be beneficial in other production cycles. Precise control of viscosity and temperature makes it possible to accurately monitor the level of evaporator residue, which in turn provides reliable information on the smooth operation of the process. By installing a MIVI viscometer, a viscosity measurement can be performed directly on the reactor or on a pipe corner, at the outlet of the evaporator or the distillation tower. The residue can be checked with the MIVI viscometer to ensure that sufficient product has been recovered. It also makes it possible to check the final quality of the product.
Inventech is happy to help you find the best viscosity analyzer for polyurethane. Contact our product manager.
