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:
Aug. 29, 1989
Filed:
Jan. 15, 1988
Applicant:
Inventor:
Fredric L Buchholz, Midland, MI (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08F / ; C08F / ;
U.S. Cl.
CPC ...
526230 ; 526234 ; 526322 ;
Abstract
This invention relates to a process for polymerizing an aqueous solution of an .alpha.,.beta.-ethylenically unsaturated monomer and at least one crosslinking monomer to produce a water-swellable polymer using sodium thiosulfate as a component of a redox initiator system. The use of sodium thiosulfate as a component of a redox initiator system for the polymerization allows for controlling the rate of initiation so as to increase the time required for gel formation during polymerization. The resulting hydrated polymer of the present invention breaks up more uniformly and with greater ease resulting in a higher per batch yield.