The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 20, 1979
Filed:
Dec. 01, 1976
Vincent F Pogozelski, Newtown, PA (US);
Robert P Conger, Park Ridge, NJ (US);
Congoleum Corporation, Milwaukee, WI (US);
Abstract
Methods of forming liquid, low viscosity, low molecular weight, cross-linkable, stable polyurethane prepolymers which comprise: reacting polyisocyanates, and preferably aliphatic and cycloaliphatic diisocyanates, with polyhydroxy compounds or polyols, and preferably diols, triols, tetrols, and mixtures thereof; the polyols having a molecular weight of from about 62 to about 3000; the polyisocyanates and the polyols being added to the reaction mixture in an NCO/OH ratio in the range of from about 0.7:1 to about 6:1, and preferably from about 1.6:1 to about 4:1; the reaction taking place preferably in an inert, non-reactive organic solvent such as xylene; in the absence of any reaction catalysts, or in the presence of a relatively very low concentration of reaction catalysts of from about 0.00005% by weight to about 0.8% by weight, based on the total weight of the reaction mixture; at a reaction temperature of from about 0.degree. C. to about 70.degree. C., and preferably from about 0.degree. C. to about 40.degree. C., for a reaction time of from about 1/2 hour to about 12 hours; and terminating the reaction short of completion at a percent completion of reaction of from about 2% to about 95%, and preferably from about 30% to about 80%. The resulting liquid, low viscosity, low molecular weight, cross-linkable, stable polyurethane prepolymers are also included in the inventive concept.