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Chaouch M.,SEREX Service de recherche et dexpertise en transformation des produits forestiers | Iaych K.,Academie des Arts traditionnels | Belakhmima R.,Universite Ibn Tofail | Ebn Touhami M.,Universite Ibn Tofail
Journal of Materials and Environmental Science | Year: 2016

The objective of this study was to evaluate the effect of heat treatment on some conferred properties of beech wood namely durability, dimensional stability, elemental composition and color, allowing the heat treated wood to implement the exterior decoration of a building. Beech boards were heat treated by conduction at 230°C for three times to achieve three mass losses due to thermo-degradation. The results showed a significant increase in the carbon content associated with a decrease of the oxygen content, a change of color, an improvement of the durability and enhancement of the dimensional stability of wood treated according to the intensity of treatment (duration). These results clearly indicated that the chemical modifications of wood cell wall polymers are directly responsible for these properties. All these modifications of wood properties were proportional to treatment intensity which is function to temperature and duration of treatment.

Iaych K.,Academie des Arts traditionnels | Dumarcay S.,University of Lorraine | Gerardin P.,University of Lorraine | Belakhmima R.,Universite Ibn Tofail | And 2 more authors.
Journal of Materials and Environmental Science | Year: 2015

Polyglycerol five membered cyclic carbonate (CPG3) was synthesized from polyglycerol, a by-product of bio-diesel production and dimethyl carbonate (DMC). CPG3 react easily with amines to yield urethane bond using a totally free isocyanate synthetic way. The use of different di and tri-amines allows the formation of polyurethanes with potential broad range of applications. The renewable origin of polyglycerol, the low toxicity of dimethyl carbonate and the experimental conditions developed involving reactions performed in good yield without solvent and without formation of by-products allow envisaging a completely green synthesis of polyurethanes.The aim behind creating polyurethane without using isocyanates has been reached, hence stressing the effectiveness of our approach. In fact, we managed to develop a biocide-free synthesis process by relying on green chemical products such as polygluceril and the dimethyle carbonate. Likewise, this process offers a very important advantage concerning the treatment that we aim to develop so as to treat wood then move on to aqueous stage.

Schorr D.,Laval University | Yoya G.K.,Laval University | Rodrigue D.,Laval University | Diouf P.N.,SEREX Service de recherche et dexpertise en transformation des produits forestiers | Stevanovic T.,Laval University
International Wood Products Journal | Year: 2015

Hardwood Kraft lignins were esterified with succinic anhydride and chemically, thermally and morphologically characterised compared to their unmodified counterparts. Esterification was confirmed by NMR and Fourier transform infrared spectrometer (FT-IR). Esterified lignins were found to be porous, less thermally stable and slightly more hydrophilic than unmodified lignins because esterification with cyclic acid anhydride is accompanied with the simultaneous liberation of carboxylic acid groups. These free carboxylic acid groups are interesting for panel production as they could create new ester groups with wood components. The wood particleboard panels were produced via compression moulding using different concentrations of unmodified and esterified Kraft lignins as sole binders (10, 20 and 30%). All the mechanical properties [impact strength, modulus of elasticity (MOE) and modulus of rupture (MOR)] of the studied wood particleboard panels significantly increased with the addition of the succinated and unmodified Kraft lignins. However, the best mechanical properties were determined for panels containing 20% of unmodified Kraft lignins. Therefore, the condensation reactions of the unmodified Kraft lignins taking place during the compression moulding seem explain why these lignins act as a more efficient binder than the succinated lignins. © 2015 IWSc.

Chaouch M.,SEREX Service de recherche et dexpertise en transformation des produits forestiers | Diouf P.N.,SEREX Service de recherche et dexpertise en transformation des produits forestiers | Laghdir A.,SEREX Service de recherche et dexpertise en transformation des produits forestiers | Yin S.,SEREX Service de recherche et dexpertise en transformation des produits forestiers
Journal of Applied Polymer Science | Year: 2014

Renewable chemicals are of growing importance in terms of opportunities for environmental concerns over fossil-based chemicals. Lignocellulosic biomass can be converted into energy and chemicals via thermal and biological processes. Among all the transformation processes available, fast pyrolysis is the only one to produce a high yield of a liquid-phase product called bio-oil or pyrolysis oil. Bio-oil is considered to be a promising substitute for phenol in phenol formaldehyde (PF) resin synthesis. In this work, bio-based phenolic resins have been formulated, partially substituting phenol by bio-oils from two Canadian whole-tree species. The new resins are produced by replacing 25, 50, and 75% of phenol with bio-oil for each species (three bioresins per species). The aim of this study is to synthesize renewable resins with competitive price and satisfactory quality. The results obtained have shown that substitution degree up to 50% provided reactivity and performance equal or superior to the pure PF resin. They also present a good storage stability, improved shear strength, and thermal stability comparable to the pure PF. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 40014. Copyright © 2014 Wiley Periodicals, Inc.

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