Temperature-sensitive hydrogels based on poly(vinyl methyl ether) (PVME) with ferroelectric or ferromagnetic properties were synthesized by high-energy irradiation. Barium titanate and poly(vinylidene fluoride) (PVDF) were used as ferroelectric filler and Ni as ferromagnetic filler. The filled PVME hydrogels were synthesized by electron beam or gamma-ray irradiation (of a suspension with 5-50 wt % of filler (with respect to polymer mass) in a 20 wt % aqueous PVME solution). Filling of the gel reduces the absolute swelling degree at low temperatures, but do not influence the phase-transition temperature of the gel. The particle distribution of the fillers inside the gel was visualized by field emission scanning electron microscopy. The fillers were incorporated in the PVME network and fixed because of their size (inorganic particles), as well as by chemical bonds (PVDF). The ferroelectric or ferromagnetic properties of the filled gels were proved. Measurements in a corresponding alternating field provide the hysteresis loop, for both the ferromagnetic and ferroelectric gel. (c) 2005 Wiley Periodicals, Inc.

Temperature-sensitive hydrogel beads were prepared by radiation crosslinking of poly(vinylmethylether) PVME spheres wrapped in Ca-alginate. The obtained gel beads have diameters in the sub-millimeter or millimeter range (depending on the PVME concentration). They were characterized by sol-gel analysis, swelling measurements, and differential scanning calorimetry.The gel content g increases with increasing radiation dose D. The swelling degree Q(V) decreases with increasing PVME concentration c(p) and increasing D. In comparison to PVME bulkgels the phase-transition temperature of the synthesized PVME gel beads is a little decreased.

Journal Article Determination of Hydrogel Structures by FESEM- Measurements Get access Daniel Theiss, Daniel Theiss Institute of Physical Chemistry and Electrochemistry, Dresden University of Technology, D- 1062 Dresden, Germany Search for other works by this author on: Oxford Academic Google Scholar Thomas Schmidt, Thomas Schmidt Institute of Physical Chemistry and Electrochemistry, Dresden University of Technology, D- 1062 Dresden, Germany Search for other works by this author on: Oxford Academic Google Scholar Dirk Kuckling, Dirk Kuckling Institute of Macromolecular Chemistry and Textile Chemistry, Dresden University of Technology, D- 1062 Dresden, Germany Search for other works by this author on: Oxford Academic Google Scholar Karl- Friedrich Arndt, Karl- Friedrich Arndt Institute of Physical Chemistry and Electrochemistry, Dresden University of Technology, D- 1062 Dresden, Germany Search for other works by this author on: Oxford Academic Google Scholar Rudolf Reichelt Rudolf Reichelt Institute of Biomedical Physics and Biophysics, University of Münster, D-48149 Münster, Germany Search for other works by this author on: Oxford Academic Google Scholar Microscopy and Microanalysis, Volume 9, Issue S03, 1 September 2003, Pages 368–369, https://doi.org/10.1017/S1431927603027144 Published: 05 September 2003