title: Grafting chitosan and polyHEMA on carbon nanotubes surfaces: "grafting to" and "grafting from" methods.
abstract: We report a simple method for engineering chitosan (CS) functionalized multi-walled carbon nanotube (MWCNT) composites with a biomedically important polymer, poly-2-hydroxyethyl methacrylate (polyHEMA), by chemical grafting HEMA monomers via free radical polymerization. Functionalization of CS and polyHEMA occurred in three steps. First, using microwave irradiation, CS was grafted onto the surface and sidewall of the carbon nanotubes. Second, HEMA monomers were grafted onto the polymeric matrix surface. The final step involved free radical polymerization of HEMA monomers. Composite synthesis was confirmed by Fourier transform infrared (FTIR) spectroscopy. Moreover, the presence of polyHEMA on the surface of the CS functionalized carbon nanotubes was confirmed by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and thermo gravimetric analysis (TGA) analyses. Furthermore, in the aqueous phase, our novel composites exhibited higher dispersibility compared with pristine MWCNTs. Considering the biomedical importance of polyHEMA and CS polymers, we expect these materials to be useful in the pharmaceutical industry as novel biomaterial composites with potential applications in drug delivery.
authors.affiliation: Department of Chemistry, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran. Electronic address: hossein.mahmoodian@gmail.com.
authors.forename: Hossein
authors.initials: H
authors.lastname: Mahmoodian
authors.affiliation: Department of Chemistry, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Omid
authors.initials: O
authors.lastname: Moradi
authors.affiliation: Department of Chemistry, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Behnam
authors.initials: B
authors.lastname: Shariatzadeh
mesh_terms: D001704:Biopolymers / Q000737:chemistry; D048271:Chitosan / Q000138:chemical synthesis* / Q000737:chemistry; D016503:Drug Delivery Systems; D006801:Humans; D008689:Methacrylates / Q000138:chemical synthesis / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008872:Microwaves; D037742:Nanotubes, Carbon / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013818:Thermogravimetry
chemical_list: D001704:Biopolymers; D008689:Methacrylates; D037742:Nanotubes, Carbon; C005044:hydroxyethyl methacrylate; D048271:Chitosan
keywords: Carbon nanotubes; Microwave; PolyHEMA