Effect of H2O and reduced graphene oxide on the structure and rheology of self-healing, stimuli responsive catecholic gels
- 725 Downloads
A catechol-containing organogel based on random copolymers of N-isopropylacrylamide (NIPAM) and dopamine methacrylate (NIDO5%) in dimethyl formamide (DMF) was supramolecularly crosslinked by NaBH4 in the presence of reduced graphene oxide (RGO). The focus of the investigations was on the influence of H2O and RGO in the system, which leads to a softening and stiffening, respectively. Whereas RGO tends to restack partially, this tendency was not found in the gels, suggesting a surface coverage of RGO with NIDO5% due to H-bonding and surface crosslinking attributed to the interactions of polar groups of polymer chains with carboxylic and carbonyl groups of RGO sheets proven by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray diffraction and spectroscopy (XRD). While RGO leads to the system becoming more brittle, its presence does not lead to an excessive loss of the self-healing characteristics, but it clearly stabilizes the gel when swollen with H2O, as can be seen from the significantly higher modulus and the retained self-healing behavior.
KeywordsSelf-healing Organogel Swelling Supramolecular bonding Reduced graphene oxide
The authors acknowledge financial aid from the National Research Foundation of Korea (110100713, 2015–020449), the National Science Foundation of China (21574086), Nanshan District Key Lab for Biopolymers and Safety Evaluation (No. KC2014ZDZJ0001A), and Shenzhen City High Level Talent Program and Shenzhen Sci & Tech research grant (ZDSYS201507141105130, JCYJ20140509172719311). The authors would also like to thank the staff of the CBNU central lab.
(AVI 21078 kb)
(AVI 25045 kb)
- D'souza F, Kadish KM (2012) Handbook of carbon nano materials, World ScientificGoogle Scholar
- Ghavaminejad A, Hashmi S, Joh HI, Lee S, Vatankhah Varnoosfaderani M, Lee YS, Stadler FJ (2014) Network formation in graphene oxide composites with surface grafted poly-N-isopropyl amide chains in aqueous solution characterized by rheological experiments. Phys Chem Chem Phys 16:8675–8685CrossRefGoogle Scholar
- Hirata M, Gotou T, Horiuchi S, Fujiwara M, Ohba M (2004) Thin-film particles of graphite oxide 1. Carbon 42(14):2929–2937Google Scholar
- Lehn J-M (1995) Supramolecular chemistry—concepts and perspectives. VCH, WeinheimGoogle Scholar
- Mingos DMP (2004) Supramolecular assembly via hydrogen bonds. Springer, BerlinGoogle Scholar