Reactive viscous media mixing and metering - by passing-compressed air first through moisture insensitive medium before sensitive medium

摘要

A medium A which is insensitive to moisture, e.g. polyol, is mixed with a medium B which is sensitive to moisture, e.g. isocyanate, by applying compressed air in series to their storage containers and to foam gun. The compressed air is first passed through the medium A and is collected above it. The dried air is passed directly or via a filter, filled with a desiccant, to the container with the medium B. This prevents any premature reaction of the isocyanate with moisture to form urea resins. The new method requires little appts. and can be easily added to existing plant.