abstract
Cholinium hexanoate, a biocompatible and biodegradable ionic liquid, was recently demonstrated to efficiently and selectively extract suberin domains from cork, combining high extraction efficiency with isolation of a partial depolymerised material. In the present paper, we report a comparative study of the characterisation of suberin extracted from birch outer bark and from cork using cholinium hexanoate. It became apparent that both extracted suberin samples showed still a cross-linked nature, i.e. likely to be closely related to in situ suberin. Suberin samples were mainly constituted by oligomeric or polymeric structures in turn essentially composed by long chain hydroxyacids monomers. Their high thermal stability together with the oligomeric/polymeric nature, open new perspectives for suberin use as macromonomers in the development of bio-based polymeric materials. This also contributes for the valorisation of suberin rich agro-forest residues. (C) 2012 Elsevier B.V. All rights reserved.
keywords
NUCLEAR-MAGNETIC-RESONANCE; SOLID-STATE C-13-NMR; QUERCUS-SUBER; THERMOGRAVIMETRIC ANALYSIS; THERMAL-DECOMPOSITION; L. CORK; METHANOLYSIS; POLYESTER; GLYCERYL; MONOMERS
subject category
Agriculture
authors
Ferreira, R; Garcia, H; Sousa, AF; Freire, CSR; Silvestre, AJD; Rebelo, LPN; Pereira, CS
our authors
acknowledgements
R.F. and A.F.S. are grateful to Fundacao para a Ciencia e a Tecnologia (FCT), Portugal, for the fellowships SFRH/BD/48286/2008 and SFRH/BPD/73383/2010, respectively; H.G. is indebted to Fundacao Calouste Gulbenkian, Portugal, for the fellowship 21-95587-B. The work was partially supported by a grant from Iceland, Liechtenstein and Norway through the EEA financial mechanism (Project PT015), and FCT through the Grants PEst-OE/EQB/LA0004/2011, Pest-C/CTM/LA0011/2011 and PTDC/QUI-QUI/120982/2010. The National NMR Network (REDE/1517/RMN/2005), was supported by POCI 2010 and Fundacao para a Ciencia e a Tecnologia, Portugal. The authors also acknowledge 7th Framework Programme FP7/2007-2013, for funding project AFORE (CP-IP 228589-2), and Thomas Holmbom (SepRes, Finland) for supplying birch outer bark samples.