Title: POLYUREA COMPOSITIONS AND METHODS OF USE
Number/Link: US20140171587
Applicant/Assignee: PRC DESOTO
Publication date: 19-06-2014 (priority PCT)
“Gist”: Sulfur-containing polyformal polyols are prepolymerized with aliphatic diisocyanates and then cured with aromatic amines.
Why it is interesting: Sulfur-containing polyformal polyols are prepared from thiodiglycol and paraformaldehyde using acidic catalysis. The polyols are then reacted with 4,4′-dicylcohexyl diisocyanate (H12MDI) to form a prepolymer which is subsequently cured with an aromatic amine like dimethylthiotoluenediamine. The resulting material is water and fuel resistant and can be used as a sealant in the aerospace industry.