@article {1867, title = { Beech wood treated with polyglycerol succinate: a new effective method for its protection and stabilization }, journal = { HOLZFORSCHUNG }, volume = {74}, year = {2020}, pages = {351-361}, abstract = {

This paper deals with an original and non-biocidal chemical treatment consisting of a vacuum/pressure impregnation step of beech wood with a water-borne mixture made from heat-activated condensation of succinic anhydride (SA) and glycerol (G). Chemical structures of adducts were established using matrix-assisted laser desorption ionization time-of-flight mass spectroscopy (MALDI-TOF) investigations. Beech wood was impregnated and cured in order to induce in situ polymerization of glycerol/succinic adducts (GSA) in the cell walls, leading to the formation of polyglycerol succinate (PGS) polyester. Various treatment conditions were investigated depending on the duration (6-72 h) and curing temperature (103-160 degrees C). Weight percent gains (WPGs) ranging between 40 and 60\% were obtained. Attenuated total reflectance-middle infrared spectroscopy (ATR-MIR) and carbon-13 nuclear magnetic resonance (C-13-NMR) spectroscopy confirmed polyester formation. A curing temperature of 160 degrees C was found to be the best condition to totally avoid polymer leaching, and brought the anti-swelling efficiency (ASE) up to 64\%. Decay resistance of PGS-treated wood against Trametes versicolor and Coniophora puteana was also strongly temperature and time dependent: performances fit with the EN113 standard requirements if a curing temperature of 160 degrees C was applied.

}, author = {C. L{\textquoteright}HOSTIS and E. FREDON and M.F. THEVENON and F.J. SANTIAGO-MEDINA and P. GERARDIN} } @article {1783, title = { Effect of polymeric diisocyanate addition on bonding performance of a demethylated-pyrolysis-oil-based adhesive }, journal = { WOOD SCIENCE AND TECHNOLOGY }, volume = {53}, year = {2019}, pages = {1311-1337}, abstract = {

After demethylation, eucalyptus pyrolysis oil has higher reactivity with formaldehyde in alkaline media than the raw oil. The objective of the present work was to evaluate the effect of adding polymeric diphenylmethane diisocyanate (PMDI) on a demethylated oil-based adhesive. Chemical composition of pyrolysis oil was determined by gas chromatography/mass spectrometry. Before and after demethylation, the eucalyptus pyrolysis oil was analyzed by carbon-13 nuclear magnetic resonance spectroscopy (C-13 NMR) and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). Demethylated oil-based adhesive was analyzed by MALDI-TOF. Plywood panels were produced with adhesives supplemented with 0, 4, 8, 16 and 20\% PMDI and an extra treatment applying a reference phenolic adhesive. The experiment encompassed six treatments with four replicates, totaling 24 panels. As demonstrated by nuclear magnetic resonance analysis, the demethylation reaction was effective in removing methyl groups from the methoxyls of syringol and derivatives, turning them, respectively, into pyrogallol and its derivatives. PMDI was effective as a cross-linking agent, enhancing the mechanical performance of the original demethylated-pyrolysis-oil adhesive. In dry condition and after boiling test, plywood manufactured with formulations adding 16 and 20\% PMDI had shear strengths statistically equal to panels bonded with the reference phenolic adhesive.

}, author = {A.S. PIMENTA and R. TRIANOSKI and A. PIZZI and F.J. SANTIAGO-MEDINA and E.C. DE-SOUZA and T.V.D. MONTEIRO and M. FASCIOTTI and R.V.O. CASTRO} } @article {1747, title = { Chemical composition of African mahogany (K. ivorensis A. Chev) extractive and tannin structures of the bark by MALDI-TOF }, journal = { INDUSTRIAL CROPS AND PRODUCTS }, volume = {113}, year = {2018}, pages = {167-178}, abstract = {

The total phenolic and the condensed tannins content of the bark, the sapwood and the heartwood of Khaya ivorensis (K. ivorensis) from the natural forest of Gabon was investigated by Folin-Ciocalteu, vanillic assay and acid/butanol methods All these methods showed that the bark, the sapwood and the heartwood of K. ivorensis did not display a significant difference (p \> 0.05) regarding their phenolic content and their condensed tannins content as well. The acetone/water extracted tannins from the bark were characterized by Matrix Assisted Laser Desorption/Ionization time of flight (MALDI-TOF) mass spectrometry and by Fourier Transform InfraRed spectroscopy (FTIR). The presence of fisetinidin, gallocatechin, and trihydroxyflavan monomers was observed for the first time. Flavonoid oligomers linked to sugars were found within K. ivorensis condensed tannins. An heptamer formed by mixed fisetinidin, trihydroxyflavan, three dihydroxyflavans, and a carbohydrate dimer including mannose was also identified for the first time in the bark of K. ivorensis. That mahogany hardwood species did not exhibit any antifungal activity against the white rot fungus Coriolus versicolor. However, bark powder decreased the radial fungus growth.

}, url = {https://hal.archives-ouvertes.fr/hal-01710611}, author = {A.B.B. ATHOMO and S.P.E. ANRIS and R. SAFOU-TCHIAMA and F.J. SANTIAGO-MEDINA and T. CABARET and A. PIZZI and B. CHARRIER} } @article {1729, title = { Destructive vs. non-destructive methods for the mechanical characterisation of tannin-based thermoset foams }, journal = { POLYMER TESTING }, volume = {69}, year = {2018}, pages = {332-339}, abstract = {

The mechanical properties of a broad range of thermoset foams based on tannin were investigated through destructive compression tests, either with or without rigid plates glued to the opposite faces of the samples, and through a rather new, non-destructive, quasi-static method. The main objective was to compare both techniques, as well as the effect of the presence of plates, and to discuss the relevance of each for properly characterising the materials. Gluing stiff plates to the samples was found to be a key point for the appropriate determination of the elastic modulus of brittle foams, whereas it did not affect that of elastic-plastic foams. In contrast, the compressive strength did not depend on the kind of test. The results obtained by destructive compression were then compared to those of the new non-destructive technique, proving that the latter was suitable for characterising elastic-plastic foams but not brittle foams. However, the new method allowed determining Poisson ratio and loss factor, which had never been measured so far for this kind of materials.

}, author = {C. DELGADO-SANCHEZ and F.J. SANTIAGO-MEDINA and V. FIERRO and A. PIZZI and A. CELZARD} } @article {1731, title = { Impact of the formulation of biosourced phenolic foams on their fire properties }, journal = { POLYMER DEGRADATION AND STABILITY }, volume = {153}, year = {2018}, pages = {1-14}, abstract = {

The fire retardance properties of rigid, biosourced phenolic foams derived from tannins, which are novel, environment-friendly thermal insulators, are essential before the latter can be applied to the building sector. In this work, tannin-based foams prepared from new formulations and using different foaming methods were investigated by thermo-gravimetric analysis (TGA), cone calorimetry, and pyrolysis combustion flow calorimeter (PCFC). It was found that the flammability strongly depends on the formulation, so that tannin foams perform very differently depending on the presence of surfactant and plasticiser and, more importantly, on their initial water content. Moreover, a good correlation was observed between TGA and PCFC results. Nevertheless, due to their highly resistant phenolic, crosslinked, polymer network, all materials released a quite low amount of hydrocarbon fuel during thermal decomposition, leading to low heat release rates and high ignition times, and thus providing very good fire retardance properties. Based on the above, the foam presenting the highest fire retardance was identified, confirming our conclusions about the role of the ingredients in the formulation.

}, url = {https://hal.inrae.fr/hal-02621928}, author = {C. DELGADO-SANCHEZ and J. SARAZIN and F.J. SANTIAGO-MEDINA and V. FIERRO and A. PIZZI and S. BOURBIGOT and A. CELZARD} } @article {1749, title = { Mechanically blown wall-projected tannin-based foams }, journal = { INDUSTRIAL CROPS AND PRODUCTS }, volume = {113}, year = {2018}, pages = {316-323}, abstract = {

Condensed flavonoid tannin-based foams from quebracho tannin extract have been developed using a new method of expansion based on fire-fighting or tunneling foams, where a foam concentrate forms a stable liquid foam. This new mechanical method of expansion allows obtaining a solid porous material after curing and hardening at room temperature, through a liquid foam formed by a tannin resin and an aqueous solution of surfactant. The stability of the as-obtained liquid foam and the influence of the amount of catalyst are reported. The use of this new approach for preparing tannin-based rigid foams avoids the problem of shrinkage presented by many other formulations where physical or chemical foaming is employed. Non-ionic surfactants have also been used in the formulation to obtain smaller cells and improve the structure of the new material. Bulk density (0.069-0.080 g/cm(3)), mechanical (compressive strength of 0.034-0.13 MPa) and thermal (0.045-0.047 W m(-1)K(-1)) properties and morphological appearance of the foams have been characterised and reported.

}, author = {F.J. SANTIAGO-MEDINA and C. DELGADO-SANCHEZ and M.C. BASSO and A. PIZZI and V. FIERRO and A. CELZARD} } @article {1735, title = { Polyurethanes from Kraft Lignin without Using Isocyanates }, journal = { JOURNAL OF RENEWABLE MATERIALS }, volume = {6}, year = {2018}, pages = {413-425}, abstract = {

The reaction of a desulphurized kraft lignin with hexamethylene diamine and dimethyl carbonate has allowed the development of isocyanate-free polyurethane resins. The present research work is based on previous studies made with hydrolyzable and condensed tannins, but takes advantage of the higher number of hydroxyl groups present in lignin and their different aliphatic and aromatic character. The obtained materials were analyzed by Fourier transform infrared (FTIR) spectroscopy, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and solid-state cross-polarization/magic angle spinning (CP MAS) C-13 nuclear magnetic resonance (NMR), which have revealed the presence of urethane functions. The interpretation of the results has shown a larger number of species than when tannins were used and has indicated the presence of two types of bonds in the new molecules formed: ionic and covalent bonds.

}, author = {F.J. SANTIAGO-MEDINA and M.C. BASSO and A. PIZZI and L. DELMOTTE} } @article {1723, title = { Projectable tannin foams by mechanical and chemical expansion }, journal = { INDUSTRIAL CROPS AND PRODUCTS }, volume = {120}, year = {2018}, pages = {90-96}, abstract = {

A new formulation of quebracho tannin-based resin has been used to prepare bio-based rigid foams. The proposed foams were blown by using the simultaneous combination of two expansion methods by mechanical expansion as used for fire-fighting foams and by chemical expansion based on the release of water and other gases during the exothermal self-condensation of furfuryl alcohol. The combination of both methods allowed us to overcome certain limitations found in the preparation of foams exclusively based on mechanical expansion These were the resulting density (16\% lower than that obtained by mechanical expansion) and the mechanical properties (compressive strength improved of about 11\%). Resin chemorheology was characterized under stressed conditions using frequency and time sweeps as well as temperature ramps. The evolution of the linear viscoelastic functions during the reaction clearly showed the transition from viscous to strong gel-like behavior. The foaming and hardening processes were followed by the use of FOAMAT equipment and the resulting foams were characterized in terms of density (0.059-0.063 g/cm(3)), mechanical properties (compressive strength of 0.090-0.144 MPa) and thermal conductivity (0.046-0.048 W m(-1) K-1).

}, author = {F.J. SANTIAGO-MEDINA and A. TENORIO-ALFONSO and C. DELGADO-SANCHEZ and M.C. BASSO and A. PIZZI and A. CELZARD and V. FIERRO and M.C. SANCHEZ and J.M. FRANCO} } @article {1700, title = { Isocyanate-Free Polyurethanes by Coreaction of Condensed Tannins with Aminated Tannins }, journal = { JOURNAL OF RENEWABLE MATERIALS }, volume = {5}, year = {2017}, pages = {21-29}, abstract = {

Isocyanate-free polyurethane resins biosourced to a very high percentage level were prepared by the reaction of aminated mimosa tannin extract with commercial mimosa tannin extract prereacted with dimethyl carbonate. The reaction took place with ease at ambient temperature. Indications were that the polyurethanes obtained formed a hard film when cured at a temperature higher than 100 degrees C. Furthermore, the carbohydrate fraction of the tannin extract also appeared to be carbonated and reacted to generate isocyanate-free polyurethane linkages with the aminated tannins. This indicated that not only the polyphenolic fraction of the tannin extract, but also its other major component, can be used to prepare polyurethane resins. Flavonoid monomers and oligomers carbonated at different levels, both unreacted and urethane-linked to aminated flavonoid monomers and oligomers, were identified by FTIR and MALDI-TOF spectrometry.

}, author = {M. THEBAULT and A. PIZZI and F.J. SANTIAGO-MEDINA and F.M. AL-MARZOUKI and S. ABDALLA} } @article {1690, title = { Polycondensation Resins by Flavonoid Tannins Reaction with Amines }, journal = {POLYMERS}, volume = {9}, year = {2017}, abstract = {

Reaction of a condensed flavonoid tannin, namely mimosa tannin extract with a hexamethylene diamine, has been investigated. For that purpose, catechin was also used as a flavonoid model compound and treated in similar conditions. Solid-state cross-polarisation/ magic-angle spinning (CP-MAS) carbon 13 nuclear magnetic resonance (C-13 NMR) and matrix assisted laser desorption ionisation time of flight (MALDI-ToF) mass spectroscopy studies revealed that polycondensation compounds leading to resins were obtained by the reaction of the amines with the phenolic hydroxy groups of the tannin. Simultaneously, a second reaction leading to the formation of ionic bonds between the two groups occurred. These new reactions have been shown to clearly lead to the reaction of several phenolic hydroxyl groups, and flavonoid unit oligomerisation, to form hardened resins.

}, author = {F.J. SANTIAGO-MEDINA and A. PIZZI and M.C. BASSO and L. DELMOTTE and A. CELZARD} } @article {1665, title = { Polycondensation Resins by Lignin Reaction with (Poly) amines }, journal = { JOURNAL OF RENEWABLE MATERIALS }, volume = {5}, year = {2017}, pages = {388-399}, abstract = {

The reaction of a desulphurized kraft lignin with hexamethylene diamine as a model of a polyamine has been investigated. For this purpose, guaiacol was also used as a lignin model compound and treated under similar conditions. Solid state CP-MAS C-13 NMR, FTIR and MALDI-TOF spectroscopy studies revealed that polycondensation compounds leading to resins were obtained by the reaction of the amines with the phenolic and aliphatic hydroxy groups of lignin. Simultaneously a second reaction leading to the formation of ionic bonds between the same groups occurred. These new reactions have been clearly shown to involve several phenolic and alcohol hydroxyl groups, as well as lignin units oligomerization, to form hardened resins.

}, author = {F.J. SANTIAGO-MEDINA and A. PIZZI and M.C. BASSO and L. DELMOTTE and S. ABDALLA} }