resumo
Modified eucalyptus kraft lignin doped with multiwall carbon nanotubes (MWCNTs) was used as a macromonomer in step-growth polymerization with tolylene 2,4-diisocyanate terminated poly(propylene glycol) with the aim of producing a conductive copolymer for all-solid-state potentiometric chemical sensor applications. The crosslinked elastomeric polyurethane obtained was characterized by Fourier transform infrared attenuated total reflection spectroscopy, scanning electron microscopy, tunnelling electron microscopy and atomic force microscopy. Doping of lignin-based polyurethane with MWCNTs produced a significant enhancement of its electrical conductivity without deterioration of thermal and viscoelastic properties. The polymer composite displayed a low percolation threshold at an MWCNT concentration of 0.18% (w/w), which was explained by the oriented distribution of MWCNTs along lignin clusters. All lignin-based polyurethanes doped with MWCNTs at concentrations above the percolation threshold are suitable for sensor applications. Copyright (c) 2012 Society of Chemical Industry
palavras-chave
KRAFT LIGNIN; COMPOSITES; METALS
categoria
Polymer Science
autores
Faria, FAC; Evtuguin, DV; Rudnitskaya, A; Gomes, MTSR; Oliveira, JABP; Graca, MPF; Costa, LC
nossos autores
Dmitry Evtyugin
Professor Associado com Agregaçãoagradecimentos
We gratefully acknowledge CICECO and CESAM Associated Research Laboratories (University of Aveiro, Portugal) and the Portuguese Science and Technology Foundation, through the European Social Fund (ESF) and