resumo
Vertically aligned carbon nanotubes (VACNTs) synthesized by Thermal Chemical Vapour Deposition (TCVD) were modified using an Ar:O-2 (97:3) plasma to generate oxygen-containing functional groups on the surface for subsequent modification. X-ray photo-emission spectroscopy (XPS) and micro-Raman analyses confirmed the grafting of those functional groups onto the surface of the nanotubes as well as the removal of amorphous carbon produced and deposited on the VACNT forests during the CVD process. The plasma treated VACNT forests were further modified with 2-bromo-2-methylpropionyl bromide, an atom transfer radical polymerization (ATRP) initiator, to grow poly(methyl methacrylate) (PMMA) chains from the forests via ATRP. Scanning transmission electron microscopy (STEM) of the ensuing VACNT/PMMA composites confirmed the coating of the nanotube forests with the PMMA polymer. 3D scaffolds of polymeric composites with honeycomb like structure were then obtained. Compressive tests have shown that the VACNT/PMMA composite has higher compressive strength than the pristine forest. (C) 2014 Elsevier B.V. All rights reserved.
palavras-chave
NANOTUBES; FUNCTIONALIZATION; NANOFIBERS
categoria
Materials Science
autores
Tebikachew, B; Magina, S; Mata, D; Oliveira, FJ; Silva, RF; Barros-Timmons, A
nossos autores
Grupos
G1 - Materiais Porosos e Nanossistemas
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
G4 - Materiais Renováveis e Economia Circular
agradecimentos
B. Tebikachew acknowledges the EMMS Erasmus Mundus Program scholarship. The authors thank Dr Antonio Cunha and Dr Antonio Fernandes of the Physics Department of the University of Aveiro, for carrying out the plasma treatment of the VACNTs and mu-Raman spectroscopy, respectively. Mrs Celeste Azevedo of CICECO/Chemistry Department of the University of Aveiro is thanked for her help with the FTIR spectra. This work was carried out with the financial support from the projects Biomaterials for Regenerative Medicine (CENTRO-07-ST24-FEDER-002030), co-financed by QREN, programme Mais Centro-Programa Operacional Regional do Ceritro and Uniao Europeia/Fundo Europeu de Desenvolvimento Regional, and PEst-C/CTM/LA0011/2013.