Hydrogels and nanogels are exciting and promising materials for many
applications due to their versatile features, such as interacting and absorbing a
significant amount of water and other solvents, excellent mechanical properties, and
adhesiveness. These materials are obtained based on the nature of the raw materials
(natural or synthetic) and the synthesis route. There are many ways to synthesize
hydrogels and nanogels; however, these routes can be classified as physical or
chemical. Physical synthesis forms a reversible cross-linking. In contrast, chemical
synthesis can generate a stable, rigid, and irreversible polymeric structure. Nowadays,
the term “smart hydrogel” has gained significant attention due to its response to
external factors, such as pH, temperature, light, electricity, and magnetic, and even an
internal approach as substrate. Besides, the characteristics and properties of these
polymeric matrices can be enhanced through the synergic relationship with
nanoparticles. The inner and outer structure and the behavior of these materials can be
studied through characterization techniques, such as light scattering, gel permeation
chromatography, viscometry, thermal analysis, spectroscopies, microscopies, and
swelling.
Keywords: Applications, Characterization, Hydrogels, Nanogels, Polymeric Matrix, Synthesis.
