Details

Autor(en) / Beteiligte

• Hradil, Jiří
• Macková, Hana
• Horák, Daniel

Titel

Polarity and Temperature-Dependent Properties of Poly(N-isopropylacrylamide) and Poly(N,N-diethylacryl-amide) Hydrogels Studied by Liquid Chromatography

Ist Teil von

• Macromolecular symposia., 2009-07, Vol.281 (1), p.142-149

Ort / Verlag

Weinheim: Wiley-VCH Verlag

Erscheinungsjahr

2009

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Superporous N-isopropylacrylamide (NIPAAm) and N,N-diethylacrylamide (DEAAm) copolymers with N,N'-methylenebisacrylamide (MBAAm) were prepared by radical polymerization with the aim to determine their temperature-dependent changes in polarity by liquid chromatography. Superpores were formed by the salt-leaching technique using NaCl as a porogen. Porosities of the hydrogels characterized by water regain and mercury porosimetry, ranging from 81 to 91%, were proportional to the volume of NaCl porogen in the feed. The retention volumes of several phenols decreased with increasing temperature as polarity of the hydrogels decreased. A jump change in solute retention volume was observed at ca. 32 °C in PNIPAAm and at ca. 35 °C in PDEAAm indicating a change in the mechanism of interaction. The Gibbs energy changes ΔGCH₂ were rather low, increasing in the order phenol < benzyl alcohol < ethanol < butan-1-ol. In contrast to the solutes, retention volumes of bovine serum albumin and dextrans were higher at higher temperature confirming thus hydrophobic interactions of the compounds with the studied hydrogels.