Poly(methacrylic acid)–copper ion interactions: Phase diagrams: light and X-ray scattering

• Published in: Polymer (Guilford) Vol. 40; no. 12; pp. 3331 - 3344
• Main Authors: Heitz, Caroline, François, Jeanne
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1999; Elsevier
• Subjects: Applied sciences; Chain conformation; Exact sciences and technology; Interactions with copper ions; Organic polymers; Physicochemistry of polymers; Poly(methyacrylic acid); Properties and characterization; Solution and gel properties; Poly(methyacrylic acid); Chain conformation; Interactions with copper ions; Polyelectrolyte; Methacrylic acid polymer; Phase diagram; Dinuclear complex; pH; Copper complex; Aqueous solution; Experimental study; Complexes; Saline solution; Conformation
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/S0032-3861(98)00126-8

The interaction of a sample of poly(methacrylic acid) with copper ions is investigated using various techniques: light and X-ray scattering, viscosimetry and fluorescence. The measurements were performed in the solubility domains and the regions where phase separation occurs were determined as a function of pH and copper/polymer ratio. We conclude that copper is mainly bound on the polymer through the formation of binuclear complexes implying pairs of adjacent carboxylates far along the chain. This induces a strong collapse of the chain at low ionisation degree and partially hinders the chain expansion at high pH. Fluorescence measurements can be interpreted through the existence of two different transitions: local and global transitions.