Process for casting polyurethane articles
A mixture of isocyanate-terminated polyurethane prepolymer made from an aliphatic diisocyanate and an approximately stoichiometric amount of a curing aromatic diamine is stored at least -5.degree. to -25.degree. C. until needed. It then is reheated to about 80.degree.-120.degree. C., at which temperature it becomes fluid and pourable. Within this temperature range the mixture has a useful life of at least about 30 minutes. Large batches of prepolymer-curing agent mixture can be prepared using existing processing equipment and techniques, analyzed and stored, then reheated and used for casting of very large articles.
Description
Patent History
Patent number: T101303
Type: Grant
Filed: Mar 2, 1981
Date of Patent: Dec 1, 1981
Inventor: Francis O'Shaughnessy (Beaumont, TX)
Application Number: 6/239,187
Type: Grant
Filed: Mar 2, 1981
Date of Patent: Dec 1, 1981
Inventor: Francis O'Shaughnessy (Beaumont, TX)
Application Number: 6/239,187
Classifications
Current U.S. Class:
With Step Of Cooling To A Temperature Of Zero Degrees C. Or Below (264/28);
To Degas Or Prevent Gas Entrapment (264/102);
264/33119;
From Reactant Having At Least One -n=c=x Group (wherein X Is A Chalcogen Atom) As Well As Precursors Thereof, E.g., Blocked Isocyanate, Etc. (528/44)
International Classification: B29C 500;
International Classification: B29C 500;
