title: Effects of precursor composition and mode of crosslinking on mechanical properties of graphene oxide reinforced composite hydrogels.
abstract: Graphene oxide (GO) is increasingly investigated as a reinforcing nanofiller for various hydrogels for biomedical applications for its superior mechanical strength. However, the reinforcing mechanism of GO in different hydrogel conditions has not been extensively explored and elucidated to date. Herein, we systematically examine the effects of various types of precursor molecules (monomers vs. macromers) as well as mode of GO incorporation (physical vs. covalent) on the mechanical properties of resulting composite hydrogels. Two hydrogel types, (1) polyacrylamide hydrogels with varying concentrations of acrylamide monomers and (2) poly(ethylene glycol) (PEG) hydrogels with varying molecular weights of PEG macromers, are used as model systems. In addition, incorporation of GO is also controlled by using either unmodified GO or methacrylic GO (MGO) which allows for covalent incorporation. The results in this study demonstrate that the interaction between GO and the surrounding network and its effect on the mechanical properties (i.e. rigidity and toughness) of composite hydrogels are highly dependent on both the type and concentration of precursors and the mode of crosslinking. We expect this study will provide an important guideline for future research efforts on controlling the mechanical properties of GO-based composite hydrogels.
authors.affiliation: Department of Chemistry, School of Natural Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea.
authors.forename: Jinhyeong
authors.initials: J
authors.lastname: Jang
authors.affiliation: School of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea.
authors.forename: Jisu
authors.initials: J
authors.lastname: Hong
authors.affiliation: School of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea. Electronic address: ccha@unist.ac.kr.
authors.forename: Chaenyung
authors.initials: C
authors.lastname: Cha
mesh_terms: D000180:Acrylic Resins; D006108:Graphite; D020100:Hydrogels; D008422:Materials Testing; D010087:Oxides; D011092:Polyethylene Glycols; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D006108:Graphite; D020100:Hydrogels; D010087:Oxides; D011092:Polyethylene Glycols; D000099166:Polyacrylamides
keywords: Graphene oxide; Methacrylic graphene oxide, Composite hydrogel; Poly(ethylene glycol); Polyacrylamide; Rigidity; Toughness