Spatial inhomogeneity in poly(acrylic acid) hydrogels |
| |
Authors: | Ilknur Yazici |
| |
Affiliation: | Department of Chemistry, Istanbul Technical University, 80626 Maslak, Istanbul, Turkey |
| |
Abstract: | The crosslink density distribution in gels known as the spatial gel inhomogeneity has been investigated in poly(acrylic acid) (PAAc) gels with the static light scattering measurements. PAAc gels were prepared at a fixed chemical crosslink density but at various initial monomer concentrations. The gels were characterized by swelling and elasticity tests as well as by light scattering measurements. PAAc gels exhibit a maximum degree of spatial inhomogeneity at a critical monomer concentration . shifts toward higher concentrations as the gel swells beyond its dilution degree after preparation. Depending on the polymer concentration in gels, swelling reduces or enhances the extent of the spatial inhomogeneities. It was shown that the apparent degree of the spatial gel inhomogeneity is determined by the combination of three effects, namely the effects of the effective crosslink density, charge density and segment density. The relative magnitudes of these effects vary depending on the polymer concentration and lead to the appearance of a maximum degree of spatial inhomogeneity at a critical concentration. |
| |
Keywords: | Poly(acrylic acid) gels Inhomogeneity Static light scattering |
本文献已被 ScienceDirect 等数据库收录! |
|