Isocyanate manufacture

Estimated HCl production during isocyanate manufacture represents net HCl. This value excludes HCl consumed ia the reaction process to make methylene diphenylene diamine (MDA) and polymethylene polyamine (PMPPA) iatermediates ia the production of 4,4 -methylenebis(phenyHsocyanate) (MDl) and polymethylene polyphenyHsocyanate (PMPPl). 

We have described a process by which small quantities of foam can be made by the prepolymer method. A number of methods are available to bring the variables involved in prepolymer making under control. We assume that the starting point for such processes is the acquisition of commercial isocyanates, polyols, and additives. Other than for audit purposes, we will assume they arrive with certification that they are of the so-called urethane grade. In the case of polyols, this typically means they contain less than 0.01% water and have good color. Free acids and low metal and chloride contents are important considerations for isocyanates. Manufacturers are well aware of the problems that will arise if these contaminants are not controlled and the materials cannot be used with confidence. 

A significant increase is expected in chlorine utilization in the manufacture of PVC and phosgenes for isocyanate manufacture. 

Polyol and Isocyanate manufactures who are active In IMR technology supply their products with the IMR agent In a totally compatible and stable form. 

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