| 摘要 |
<p>Hydrolyzable chloride in toluene diisocyanate (TDI), distillation bottoms is reduced by heating crude TDI, optionally in the presence of a solvent, to cause: (a) partial reflux, (b) partial reflux and fractionation, or (c) complete reflux and fractionation and/or by contacting toluene diisocyanate distillation residue with a material suitable for purging chloride-containing vapors under reaction conditions suitable to remove chloride-containing vapors from the toluene diisocyanate distillation residues. Viscosity-stable and reactive bottoms, from either process, can be reacted with compounds containing active hydrogen to form polyurethane, polyurea, and polyisocyanurate polymers, particularly foamed polymers.</p> |
