Hysteresis-like behaviour in the swelling/deswelling of polystyrene based crosslinked resins using acetone/water mixtures

✍ Scribed by S. Roe; D.C. Sherrington

• Book ID: 103073587
• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 320 KB
• Volume: 23
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(87)90073-5

✦ Synopsis

Five polystyrene resins nominally ~20% crosslinked and macroporous (toluene diluent/comonomers, 2/1) have been prepared. Four of these have a nominal content of ~5% v/v respectively of methacrylic acid, 4-vinyl pyridine, 2-hydroxyethyl methacrylate and methyl methacrylate. The swelling behaviour of each in tetrahydrofuran/water and acetone/water mixtures of 80, 60, 40 and 20% by volume has been quantified. In the former mixtures, the swelling achieved is independent of whether pre-mixed solutions are used, or whether either pure component contacts the resins first. Unique swelling/composition curves result. With acetone and water, however, the swellings using pre-mixed solutions and solutions where water contacts the resin first, are depressed relative to those where acetone contacts the resin first. Two different swelling/composition curves result for each resin, forming an hysteresis-like loop. This result is explained tentatively in terms of a kinetic effect and differences in the strengths of interaction between tetrahydrofuran and water, and acetone and water.