What reaction occurs between carboxyl groups and divalent ions that reduces the equilibrium swelling of the hydrogel?
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The reaction between carboxyl groups and divalent ions leads to chelation, reducing the equilibrium swelling of the hydrogel. This process involves the formation of metal ion complexes with carboxylic acid groups, strengthening the crosslinking within the gel network and enhancing its stability and viscoelasticity . Divalent metal ions trigger gel collapse and affect the structure and swelling behavior of the hydrogel systems, with a minimum concentration of around 0.1 mM required to induce gel collapse . Additionally, the presence of divalent salts influences the swelling properties and gel fraction of hydrogels, with higher gelation capacity observed in the presence of divalent salts compared to monovalent salts . The interplay between carboxyl groups and divalent ions plays a crucial role in modulating the equilibrium swelling behavior of hydrogels.
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69 Citations | The reaction between carboxyl groups and divalent ions leads to gel collapse and the formation of a heterogeneous nanostructure, reducing equilibrium swelling of the hydrogel. |
Open access•Journal Article 9 Citations | The reaction between carboxyl groups and divalent ions forms stronger cross-links, reducing the equilibrium swelling of the hydrogel prepared with carboxymethyl cellulose under irradiation. |
32 Citations | The absorption of divalent ions by carboxyl groups leads to reduced equilibrium swelling of the hydrogel due to ionic binding affinities and transient divalent crosslinking. |
Open access•Dissertation 01 Jan 2015 4 Citations | Chelation of divalent ions by carboxyl groups reduces equilibrium swelling of gelatin hydrogels, enhancing stability and viscoelasticity by strengthening crosslinking interactions in the gel network. |
3 Citations | The reaction between carboxyl groups and divalent ions triggers gel collapse, reducing hydrogel swelling. This interaction was quantified, with a minimum 0.1 mM concentration needed for gel collapse. |
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