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Celzard A.,CNRS Jean Lamour Institute | Szczurek A.,CNRS Jean Lamour Institute | Jana P.,CNRS Jean Lamour Institute | Fierro V.,CNRS Jean Lamour Institute | And 5 more authors.
Journal of Cellular Plastics | Year: 2015

Tannins are non toxic, cheap and abundant polyphenolic oligomers extracted from tree barks. They can be easily used for preparing thermoset resins that are natural at the 70-95% level, depending on the cases. From these resins, highly porous monoliths can be obtained by different techniques such as classical physical or chemical foaming, mixed physical/chemical foaming, by less-conventional methods such as emulsion-templating and stabilisation and hardening of either aerated emulsions or liquid foams. The resultant materials are not only interesting per se, but are also key precursors of novel cellular carbons having a broad range of applications. The present paper briefly reviews the latest advances for producing tannin-based cellular materials and their related characteristics and properties. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav. Source


Basso M.C.,Indunor | Basso M.C.,University of Lorraine | Lacoste C.,University of Lorraine | Pizzi A.,University of Lorraine | And 3 more authors.
Industrial Crops and Products | Year: 2014

Highly flexible films and strongly adhering surface finishes were prepared by reacting partially aminated polyflavonoid tannins with furfuryl alcohol in the presence of plasticisers such as glycerol or polyethylene imine. 13C NMR analysis showed partial amination of the tannin under the conditions used and even the formation of some N bridges between flavonoids, although these were shown to be rare. MALDI-TOF analysis showed the presence of oligomers produced by the reaction of furfuryl alcohol with the flavonoids and the simultaneous self-condensation of furfuryl alcohol. Thus linear methylene-furanic chains were also found to be linked to flavonoid reactive sites. Furthermore, side condensation reactions of furfuryl alcohol lead to the formation of methylene ether bridges between furanic nuclei, followed by rearrangement to methylene bridges with liberation of formaldehyde. This latter reacts with both the reactive sites of the flavonoid and of the furane rings to yield CH2OH and CH2 + groups and methylene bridges. © 2014 Elsevier B.V. Source


Basso M.C.,Indunor | Giovando S.,Indunor | Pizzi A.,University of Lorraine | Pizzi A.,King Abdulaziz University | And 2 more authors.
Industrial Crops and Products | Year: 2013

Prorobinetinidin/profisetinidin type tannins have been used to prepare self-blowing tannin/furfuryl alcohol foams that do not need either formaldehyde or volatile organic blowing agents to prepare rigid foams. The 98% renewable materials foams so produced were even more environment-friendly, they presented equal thermal insulation and fire resistance and presented better stress-strain characteristics than tannin/furanic foams containing formaldehyde and organic blowing agents. Comparison of curves describing the simultaneously-measured foams expansion, hardening, temperature and pressure variation as a function of time allowed to show the differences in process and foaming parameters engendered by the differences in formulation of the experimental and control foams and optimisation of the foaming and hardening parameters involved. Tomography of the foams and foam controls produced supported the different characteristics observed for these foams obtained by stress-strain curves in compression. © 2013 Elsevier B.V. Source


Basso M.C.,Indunor | Giovando S.,Silva Chimica | Pizzi A.,University of Lorraine | Pizzi A.,King Abdulaziz University | And 4 more authors.
Journal of Applied Polymer Science | Year: 2014

Open cell foams obtained by the simultaneous coreaction of condensed flavonoid tannins with an alkoxylated fatty amine and polymeric diphenylmethane isocyanate yielded highly flexible/elastic polyurethane foams. Copolymerized amine/isocyanate/tannin oligomers were identified by 13C NMR and MALDI-TOF spectroscopy. In general, between 30% and 50% of natural tannins is added to the components used to obtain polymerisation of the polyurethane. The characteristic of these new, partially biosourced polyurethanes is that the tannin present slows down burning, some of them can be made flame self-extinguishing and if burning they neither flow nor asperge flaming material around, contrary to what occurs with normal polyurethanes. This limits the possibility of transmitting fire to other materials in the same environment. Cyclic compression tests were carried out showing that after 50 cycles foam recovery was in excess of 80%. Copyright © 2014 Wiley Periodicals, Inc. Source


Lacoste C.,University of Lorraine | Pizzi A.,University of Lorraine | Pizzi A.,King Abdulaziz University | Basso M.-C.,Indunor | And 3 more authors.
Industrial Crops and Products | Year: 2014

New formulations of procyanidin tannin-based foams have been developed for the first time with maritime pine (Pinus pinaster) tannins. These tannins have an extremely high reactivity which makes them difficult to use for traditional tannin-based foams. For this work, an equipment named FOAMAT was used to record simultaneously temperature, pressure, velocity and dielectric polarization during foaming. The results highlight the role of surfactant (castor oil ethoxylate) and plasticizer (Polyethylene glycol) during foam formation: polymerization, expansion, hardening, and shrinkage. In this work, foams density - and its physical properties - are either surfactant or plasticizer-controlled. With polyethylene glycol and castor oil ethoxylate, homogeneous microstructure foams were obtained but polyethylene glycol made the foams more elastic and improved their shrinkage. © 2013 Elsevier B.V. Source

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