Preparation of superabsorbent polymers by crosslinking acrylic acid and acrylamide copolymers

✍ Scribed by Z. S. Liu; G. L. Rempel

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 248 KB
• Volume: 64
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19970516)64:7<1345::aid-app14>3.0.co;2-w

✦ Synopsis

High water-absorbent copolymers comprising acrylic acid (AA) and acrylamide (AM) were prepared in the presence of a crosslinking agent, monofunctional aldehyde, by a solution polymerization technique using a redox initiation system. Such copolymers have very high water absorbency and absorbing kinetics to the distilled water. The copolymer formed which absorbed about 900 g water/g dry copolymer was used to study the influence of sodium chloride on the absorption capacity at 24ЊC. The swelling of this copolymer was studied in alcohol/water mixtures of increasing alcohol content at 294, 304, and 314 K. The main transition for ethanol/water and methanol/ water mixtures is a rapid decrease of the retention capacity of the copolymer at 50-60 vol % ethanol and 55-65 vol % methanol, respectively. Swelling in distilled water at different temperatures ( T ) and the effect of solvent composition were also studied. Among the variables examined were initiator concentration, polymerization temperature, and amount of AM in the copolymer.