A Review on Synthesis Methods of Phyllosilicate- and Graphene-Filled Composite Hydrogels

Abstract

This review discusses, in brief, the various synthetic methods of two widely-used nanofillers; phyllosilicate and graphene. Both are 2D fillers introduced into hydrogel matrices to achieve mechanical robustness and water uptake behavior. Both the fillers are inserted by physical and chemical gelation methods where most of the chemical gelation, i.e., covalent approaches, results in better physical properties compared to their physical gels. Physical gels occur due to supramolecular assembly, van der Waals interactions, electrostatic interactions, hydrophobic associations, and H-bonding. For chemical gelation, in situ radical triggered gelation mostly occurs.

Nanofibrous electrospun scaffold doped with hydroxyapatite derived from sand lobster shell (Panulirus homarus) for bone tissue engineering

“…38,39 Moreover, the HAp is an anisotropic ller in the nanober, which is a desirable ller to improve the mechanical properties and uniaxial stretching strength in terms of stress distribution. 53,54 The incorporation of HAp into the nanober acts as stress dissipation, resulting in delayed network rupturing, leading to the nanober's less fatigue behavior. 53…”

Novel Photothermal Graphene-Based Hydrogels in Biomedical Applications

“…For graphene/hydrogel incorporation, physical interactions such as hydrophobic interactions, π–π stacking, hydrogen bonding, self-assembly, or crystallization take place. When self-assembly method is used, the obtained materials present characteristics, such as high thermal stability, a porous structure, and an ultra-low density [ 44 ]. Furthermore, another simple method of forming physical crosslinks is crystallization that occurs after repeated freezing and thawing cycles under certain conditions.…”

Doped Carbon Quantum Dots Reinforced Hydrogels for Sustained Delivery of Molecular Cargo

“…Due to insufficient stress dissipation, lack of homogeneity in reinforcement, and poor thermal stability, the service life of polymer composites is occasionally compromised. Several studies have used nanoclay, graphene platelets, silica, graphene oxide (GO), nanodiamonds, CNTs, and other fillers in polymer matrices [ 67 , 68 , 69 , 70 , 71 , 72 ]. In this sense, CQDs play an essential role in resolving the aforementioned shortcomings.…”