Reinforced Hydrogels via Carbon Nitride Initiated Polymerization

Abstract

The utilization of graphitic carbon nitride (g-CN) as photoinitiator for hydrogel formation is reported. On top of the photochemical activity, g-CN entails the role of a reinforcing agent. Hydrogels formed via g-CN (0.6 wt % g-CN and 11 wt % solid content in total) possess significantly increased mechanical strength, around 32 times stronger storage moduli (from 250 Pa for the reference sample up to 8300 Pa for g-CN derived hydrogels) than the ones initiated with common radical initiators. In addition, the g-CN derived hydrogels show mechanical properties that are pH dependent. Therefore, g-CN acts as a photoinitiator for hydrogel formation and as reinforcer at the same time.

Extremely Compressible Hydrogel via Incorporation of Modified Graphitic Carbon Nitride

“…Reversible assembly of g‐CN particles in water was shown to provide hydrogel‐like 3D networks, presenting dye absorption and degradation platforms . Recently, it was employed in polymer chemistry to perform photopolymerization or fabricate hydrogels . It was shown that g‐CN sheets act as reinforcer and photoinitiator in radical mediated hydrogel formation with surface charge being one of the important parameters regarding hydrogel strength .…”

“…Recently, it was employed in polymer chemistry to perform photopolymerization or fabricate hydrogels . It was shown that g‐CN sheets act as reinforcer and photoinitiator in radical mediated hydrogel formation with surface charge being one of the important parameters regarding hydrogel strength . Our group recently developed a one pot grafting method to anchor functional groups on the surface of g‐CN, showing excellent dispersions in aqueous and organic media .…”

“…Similar to the optimum monomer ratio, there is also an optimum amount of g‐CN‐AHPA incorporation to balance between stiffness of the hydrogel and elasticity. Conclusively the negative charge on the g‐CN surface plays an important role for reinforcement . Thus, swelling of 2 wt% g‐CN‐AHPA hydrogels in salt solutions (0.2 m in NaCl or CaCl 2 ) was performed.…”

Photo‐Induced Hydrogel Formation Based on g‐C3N4 Nanosheets with Self‐Cross‐Linked 3D Framework for UV Protection Application

“…Recently, graphitic carbon nitride (g‐C 3 N 4 ) as metal‐free semiconductor has attracted extensive attention . It has been successfully used to reinforce hydrogels, and meanwhile bestowed additional properties on the obtained composite hydrogels . Nevertheless, the current synthetic process is relatively complex and needs external initiators or cross‐linkers.…”

Pure hydrophilic block copolymer vesicles with redox- and pH-cleavable crosslinks

“…In order to preserve the completely hydrophilic self-assemblies crosslinking in aqueous solution is a valid option as it has been utilized frequently in nano particle 29,30 and hydrogel formation. 31,32 In the case of DHBC-based systems crosslinking has been performed with self-assemblies from PEO-b-poly(N-vinylpyrrolidone) (PEO-b-PVP) 33 and PEO-b-PEtOx. 34 A bio-derived building block that has proven to be useful in DHBC self-assembly so far is Pull, 20,21 which is a linear nonionic poly(saccharide) consisting of α-1,6-linked maltotriose units.…”