Authors Meyer, T. ; Hellweg, T. ; Spange, St. ; Hesse, S. ; Jäger, C. ; Bellmann, C.
Title Synthesis and Properties of Crosslinked Polyvinylformamide and Polyvinylamine Hydrogels in Conjunction with Silica Particles
Date 27.09.2002
Abstract Polyvinylamine hydrogels with silica particles encapsulated (PVAm/silica) were produced by a two-step synthesis. In the first step, polyvinylformamide/silica (PVFA/silica) hybrids were synthesized from vinylformamide (VFA) and 1,3-divinylimidazolidin-2-one (1,3-bisvinylethyleneurea, BVU), as the crosslinker, by radical copolymerization in silica/water suspensions using different compositions of VFA/BVU. The target product PVAm/silica was obtained by acidic hydrolysis of the PVFA/silica hydrogels in a second step. The chemical structures of both hydrogels, PVFA/silica and PVAm/silica, respectively, were revealed by solid-state <SUP>13</SUP>C(<SUP>1</SUP>H) cross-polarity/magic-angle spinning NMR spectroscopy. Both hydrogels swelled significantly in water. The swelling capacity of the two systems was characterized by the correlation length <IMGSRC="/giflibrary/12/xi.gif"BORDER="0"> (or hydrodynamic blob size) of the network meshes with small-angle neutron scattering experiments. <IMGSRC="/giflibrary/12/xi.gif"BORDER="0"> is significantly larger for PVAm/silica than for PVFA/silica, which corresponds to the observed higher swelling capacity of this polyelectrolyte material. Furthermore, t<br />he swelling behavior of the hybrid hydrogels was quantitatively described in terms of free swell capacity, centrifuge-retention capacity, adsorption against pressure, and free swell rate as compared with values of the corresponding copolymer hydrogels. &copy; 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3144-3152, 2002
Journal Journal of Polymer Science: Part A: Polymer Chemistry 40 (2002) 3144-3152

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