24 августа, 2015 
Malyar The versatility of isocyanate chemistry provides many avenues for synthetic manipulation and product development. Just a few of many examples are mentioned below.
1. Emulsifiable pMDI
Polymeric MDI adhesives are rendered water emulsifiable through reaction with hydrophilic chains such as polyethylene oxide, as shown below.
Monofunctional hydroxyl terminated polyethylene oxide chains with degree of polymerization from 5 to 20 are reacted with pMDI, or simply with MDI, to provide surface active agents. The resulting surface active agent is then mixed with pMDI to provide a resin which is dispersible in water, resulting in an oil-in-water emulsion [51]. Such emulsions are stable for brief periods, 1 to 2 hours, before the water reaction causes gelation. Emulsifiable pMDI could be used where dispersion in water offers some benefit. For example, neat emulsifiable pMDI could be added directly to the blow line for medium density fiberboard production. Water emulsified pMDI has been used for improving resin distribution in particleboard or OSB manufacture; however, this is not common industrial practice.
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