Chemical Modification of Carbon Nanofibers with Plasma of Acrylic Acid

• Published in: Plasma processes and polymers Vol. 10; no. 7; pp. 627 - 633
• Main Authors: Neira-Velázquez, María G., Hernández-Hernández, Ernesto, Ramos-deValle, Luis F., Ávila-Orta, Carlos A., Perera-Mercado, Yibran A., Solís-Rosales, Silvia G., González-Morones, Pablo, Ponce-Pedraza, Arturo, Ávalos-Borja, Miguel, Narro-Céspedes, Rosa I., Bartolo-Pérez, Pascual
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01.07.2013; Wiley-VCH; Wiley Subscription Services, Inc
• Subjects: Acids; Acrylic acid; Acrylics; Applied sciences; Chemical bonds; Chemical industry; Composites; Deposition; Dispersions; Exact sciences and technology; Forms of application and semi-finished materials; Nanocomposites; Nanomaterials; Nanostructure; Plasma; Polymer industry, paints, wood; Spectrum analysis; Technology of polymers; X-ray photoelectron spectroscopy; Polyelectrolyte; Molecular structure; Morphology; Acrylic acid polymer; Nanocomposite; Manufacturing; Experimental study; Glow discharge polymerization; Carbon fiber
• ISSN: 1612-8850; 1612-8869
• DOI: 10.1002/ppap.201200122

Hydrophilization of carbon nanofibers (CNFs) was achieved using plasma polymerization of acrylic acid. Transmission electron microscopy (TEM) and spectroscopy techniques were used to assess the structural changes and type of chemical groups grafted on CNFs during plasma treatment. Electron energy loss spectroscopy analysis showed a decrease of sp2 bonds and an increase of sp3 bonds coming from the thin film of polyacrylic acid deposited on CNFs during the plasma treatment. X‐ray photoelectron spectroscopy (XPS) corroborated that the sp2/sp3 ratio of the treated CNFs decreased from 3.95 to 1.14. Also the presence of carbonyl and carboxyl groups were identified by XPS, whose presence promotes the hydrophilic character of CNFS and their dispersion in water. An amorphous structure on the surface of treated CNFs, which corresponds to the nanocoating of polyacrylic acid deposited by plasma, was observed by TEM. Plasma treatment of CNFs using acrylic acid promotes their hydrophilic character. This new surface property of CNFs is a result of an increase of oxygen concentration at the surface of treated CNFs which has been demonstrated by XPS and EELS spectroscopy. A crosslinked nanocoating of polyacrilic acid was deposited on the surface on CNFs and part of this nanofilm was chemically bonded to the carbon atoms of the CNFs. The dispersion of plasma treated CNFs in water was stable.