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:
Dec. 28, 1993
Filed:
Jun. 15, 1992
Hanno R van der Wal, Kreeksingel, NL;
The Dow Chemical Company, Midland, MI (US);
Abstract
A process for the recovery of scrap polyurethane polymer in the form of a polyol, and the use of said polyol to prepare a fresh polyurethane polymer. Said process involves thermally treating scrap polyurethane at an elevated temperature with a liquid mixture which consists of an alkanolamine and a metal hydroxide and subsequently reacting the resulting intermediate product with an alkylene oxide comprising propylene oxide to obtain polyol. The recovery process is characterized in that the weight ratio of scrap polyurethane to liquid mixture is from at least 12:1, and the liquid mixture contains the alkanolamine in from about 70 to about 95 weight percent. The recovered polyol can be used to prepare fresh polyurethane foam that exhibits enhanced physical properties at a reduced isocyanate consumption compared to similar foam prepared in the absence of any recovered polyol.