Physical crosslinking
occurs via noncovalent interactions, whereas chemical crosslinking
utilizes covalent interactions. The degree of crosslinking influences
the area permitted for diffusion across the hydrogel network, and
consequently, the water uptake capacity of hydrogels. Generally,
the greater the degree of crosslinking, the lesser the resulting
swelling ability and the adsorption capacity of hydrogels (Peppas
et al., 2010; Hennink and van Nostrum, 2012).