| http://www.w3.org/ns/prov#value | - The reduction in pressure facilitates the removal of the dissolved gases such as nitrogen and carbon dioxide, and then the ingredients are preferably reacted in a polymerization oven at between about 120??? and 150??? C. (e.g., 143??? C.) in the absence of a urethane-forming catalyst and the reaction continued until there are substantially no free isocyanate groups, e.g., 1/2 hr.-48 hours, more ty
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