Determination of average molecular weight between cross-links ( [formula omitted]) from swelling behaviours of diprotic acid-containing hydrogels

• Published in: Polymer (Guilford) Vol. 40; no. 11; pp. 2969 - 2974
• Main Authors: Sen, Murat, Yakar, Arzu, Güven, Olgun
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.05.1999; Elsevier
• Subjects: Applied sciences; Exact sciences and technology; Hydrogel; Molecular weight between cross-links; N-Vinyl 2-pyrrolidone/itaconic acid copolymer; Organic polymers; Physicochemistry of polymers; Properties and characterization; Solution and gel properties; N-Vinyl 2-pyrrolidone/itaconic acid copolymer; Molecular weight between cross-links; Hydrogel; Molecular structure; Swelling; Crosslink density; Experimental study; Itaconic derivative copolymer; Colloidal gel; Acrylamide copolymer; Pyrrolidone(vinyl) copolymer; pH; Acid copolymer; Maleic acid copolymer; Thermodynamic properties; Interaction parameter
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/S0032-3861(98)00251-1

Determination of average molecular weight between cross-links ( M c ) of itaconic acid-containing poly(vinyl pyrrolidone) and maleic acid-containing poly(acrylamide) hydrogels sensitive to pH changes of the swelling medium was investigated. Poly-electrolyte hydrogels with varying compositions were prepared in the form of rods from ternary mixtures of N-vinyl 2-pyrrolidone/itaconic acid/water and acrylamide/maleic acid/water. Gelation was achieved by irradiating the system with γ rays at ambient temperature. The equation modified by the authors recently for the determination of M c is observed to describe very well the swelling behaviour of charged polymeric networks. In addition to the evaluation of M c from swelling data, the same equation also provides the simultaneous measurement of polymer–solvent interaction parameter of the systems investigated.