Discontinuous Volume Transitions in Cross-Linked Polyelectrolyte Gels Induced by Short-Range Attractions and Strong Electrostatic Coupling

• Published in: Macromolecules Vol. 37; no. 10; pp. 3850 - 3856
• Main Authors: Schneider, Stefanie, Linse, Per
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 18-05-2004
• Subjects: Applied sciences; Chemical Sciences; Exact sciences and technology; Fysikalisk kemi; Kemi; Natural Sciences; Naturvetenskap; Organic polymers; Physical Chemistry; Physicochemistry of polymers; Properties and characterization; Solution and gel properties; Colloidal gel; Polyelectrolyte; Monte Carlo method; Swelling; Computer simulation; Theoretical study; Phase transitions
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/ma035512n

The swelling behavior of polyelectrolyte gels with and without short-range attraction was studied at variable permittivities using Monte Carlo simulations. The primitive model, with explicit treatment of all charged species augmented with an attractive square-well potential between network particles, was used. Discontinuous volume transitions appeared at critical values of the depth of the square-well potential at fixed permittivity and at critical values of the permittivity at fixed short-range potential. In particular, we observed such a transition also without the short-range potential. The collapsed state was favored by the short-range attraction and/or at low permittivity. The volumes of the collapsed states were 1−2 orders of magnitude smaller than those of the swollen states.