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Updated: Jan 26, 2026
Preparation of DNA-crosslinked Polyacrylamide Hydrogels
Published on: August 27, 2014
Influence of Network Structure on the Crystallization Behavior in Chemically Crosslinked Hydrogels
Zhenfang Zhang1,2,3, Qian Li4,5, Cigdem Yesildag6
1State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China. lawrencezzf@hotmail.com.
Abstract:
The network structure of hydrogels is a vital factor to determine their physical properties. Two network structures within hydrogels based on eight-arm star-shaped poly(ethylene glycol)(8PEG) have been obtained; the distinction between the two depends on the way in which the macromonomers were crosslinked: either by (i) commonly-used photo-initiated chain-growth polymerization (8PEG⁻UV), or (ii) Michael addition step-growth polymerization (8PEG⁻NH₃). The crystallization of hydrogels is facilitated by a solvent drying process to obtain a thin hydrogel film. Polarized optical microscopy (POM) results reveal that, while in the 8PEG⁻UV hydrogels only nano-scaled crystallites are apparent, the 8PEG⁻NH₃ hydrogels exhibit an assembly of giant crystalline domains with spherulite sizes ranging from 100 to 400 µm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses further confirm these results. A model has been proposed to elucidate the correlations between the polymer network structures and the crystallization behavior of PEG-based hydrogels.
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