Superabsorbent polymers and methods of making the same

US8895683B2 · kind B2 · utility

Assignee

• EVONIK DEGUSSA GMBH · DE

Inventors

• Franz-Felix Kuppinger · Marl, DE
• Axel Hengstermann · Senden, DE
• Guido Stochniol · Haltern am See, DE
• Gunther Bub · Marl, DE
• Jurgen Mosler · Marl, DE
• Andreas Sabbagh · Dülmen, DE

Key dates

• Filing date: May 17, 2013
• Grant date: Nov 25, 2014
• Expiry date: May 24, 2033

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/10
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

In one aspect, a process for the preparation of a superabsorbent polymer is described herein. In some embodiments, the process comprises (I) preparing acrylic acid, wherein the process comprises (a1) provision of a fluid F1 having a composition comprising from about 5 to about 20 wt. % of hydroxypropionic acid, salts thereof, or mixtures thereof; from about 0.1 to about 5 wt. % of inorganic salts; from about 0.1 to about 30 wt. % of organic compounds which differ from hydroxypropionic acid; from 0 to about 50 wt. % of solids; and from about 20 to about 90 wt. % of water; (a2) dehydration of said hydroxypropionic acid to give a fluid F2 containing acrylic acid; and (a3) purification of said fluid F2 to give a purified acrylic acid phase comprising acrylic acid having a purity of at least 70 wt. %; and (II) polymerizing the acrylic acid of (I) to form a superabsorbent polymer.