@article {1889, title = { Biosourced heat resistant coatings by cross-linking of proteins with triethyl phosphate }, journal = { PROGRESS IN ORGANIC COATINGS }, volume = {138}, year = {2020}, abstract = {

The industrial application of proteins has been limited so far. While there are good possibilities to develop protein-based products like adhesives and coatings. The paper deals with using wheat protein hydrolysate, namely SOLPRO 508 and casein reacted with triethyl phosphate (TEP) for the preparation of high-temperature resistance coatings.

The Result of Matrix-Assisted Laser Desorption-Ionization - Time Of Flight (MALDI-ToF) and Attenuated Total Reflectance- Fourier Transform Mid-Infrared (ATR-FT MIR) spectroscopy confirmed that wheat protein and casein had the ability to react with triethyl phosphate. Moreover, the related coatings present outstanding adhesion and excellent solvent resistance.

}, author = {S. AMIROU and A. PIZZI} } @article {1885, title = { Oxidized demethylated lignin as a bio-based adhesive for wood bonding }, journal = { JOURNAL OF ADHESION }, year = {2020}, abstract = {

Lignin was successfully modified to prepare a bio-based wood adhesive by just two synthesis steps: demethylation and periodate oxidation. Fourier Transform Infrared Spectroscopy (FT-IR), Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) Mass Spectrometry and Thermomechanical Analysis (TMA) were combined to characterize the bio-based adhesives obtained. Furthermore, the adhesion performance of the bio-based lignin adhesive was measured by testing the tensile shear strength of the bonded joints. The results show that demethylated lignin gives to the wood joint acceptable dry shear strength, but no wet shear strength. Thus, sodium peroxide (NaIO4) oxidant was used to improve the bonding performance of lignin-based adhesives. The optimal formulation for oxidized demethylated lignin adhesives was found to be by 20\% addition of NaIO4. The adhesive presented is a lignin-derived non- aldehyde addition, high biomass content, and its preparation is convenient, low-cost product and can be applied to wood bonding.

}, author = {X.Y. CHEN and X.D. XI and A. PIZZI and E. FREDON and G.B. DU and C. GERARDIN and S. AMIROU} } @article {1812, title = { African tree bark exudate extracts as biohardeners of fully biosourced thermoset tannin adhesives for wood panels }, journal = { INDUSTRIAL CROPS AND PRODUCTS }, volume = {132}, year = {2019}, pages = {253-268}, abstract = {

A totally \"bio\" hardener derived from the exudate extract of the African trees Vachellia nilotica and Senegalia senegal was investigated. It hardened a maritime pine tannin resin without any obvious presence of an aldehyde thus obtaining a completely \"bio\" adhesive for wood panels. MALDI-ToF and CP MAS C-13 NMR analysis indicated that the hardeners cross-linking species was 2,5-dihydroxymethyl furan linked onto carbohydrate chains. The hydroxymethyl furan moieties reacted both after detachment from the carbohydrate chains but also with carbohydrate chains still attached. The carbohydrates too were then involved as part of the binder. The gel times were slower than what was obtainable with paraformaldehyde but sufficiently fast to possibly be of industrial significance.

}, author = {B. NDIWE and A. PIZZI and B. TIBI and R. DANWE and N. KONAI and S. AMIROU} } @article {1808, title = { Glutaraldehyde-wheat gluten protein adhesives for wood bonding }, journal = { JOURNAL OF ADHESION }, year = {2019}, abstract = {

Wheat gluten protein hydrolysate was used as a biomass feedstock to prepare environmentally friendly protein-based adhesives, with hydrolyzed wheat protein as control. Glutaraldehyde was used to modify it to obtain a glutaraldehyde-wheat protein (GP) adhesive. Polyethylenimine (PEI) was also used as a crosslinking agent. Plywood has been prepared and tested, and its performance was used to measure the wheat gluten protein hydrolysate adhesive bonding performance. Differential scanning calorimetry (DSC) and thermomechanical analysis (TMA) were used to analyze the adhesive thermal properties and the microstructures of the cured adhesives by scanning electron microscopy (SEM). The results show that modification by glutaraldehyde can effectively improve the bonding performance of wheat protein adhesives, the plywood bonded strength having been improved by its addition. The effect of PEI as a crosslinking agent became evident. It can greatly improve the bonding properties of glutaraldehyde-modified wheat protein adhesives. TMA analysis indicates that the glutaraldehyde-modified GP adhesive has a higher storage modulus than the unmodified one. The modulus of the adhesive increased after adding the PEI cross-linking agent.

}, author = {X.D. XI and A. PIZZI and C. GERARDIN and J.J. LIAO and S. AMIROU and S. ABDALLA} } @article {1801, title = { Investigations of mechanical properties and chemical changes occurring during welding of thermally modified ash wood }, journal = { JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY }, volume = {34}, year = {2019}, pages = {13-24}, abstract = {

Heat treatment of wood appears as an ecological and environmentally friendly alternative in the field of wood treatment. Generally, thermal modification increase dimensional stability by reduces of hygroscopicity and water absorption but it makes it difficult to bonding in some application. During welding, changes in the morphological, chemical, and physical properties of the wood cell wall are observed due to the compression and high temperatures produced by welding. Also, the degradation of cell wall in the wood causes some mechanical properties are reduced. This modification appears without any effect on the linear welding of thermal-ash wood. Scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) were used for evaluation of properties of wood-welding systems and their interactions. The mass spectrometry (MS) analysis was used to identifying the organic degradation products emitted during welding of thermo-ash. The results of experiments show that the use of friction welding for the bonding of thermal ash wood in dry conditions was possible, and we had good results. The best combination was with a welding time of 3.5 s devised to 0.5 s and 3 s and welding pressure 2.5 and 4 MPa, respectively. The result obtained is comparable to the result obtained with EPI adhesives. Welding time greater than 3.5 MPa negatively affects the welding quality and gives low the mechanical strength.

}, author = {S. AMIROU and A. PIZZI and L. DELMOTTE} } @article {1787, title = { Particleboard bonded with bio-hardeners of tannin adhesives }, journal = { EUROPEAN JOURNAL OF WOOD AND WOOD PRODUCTS }, volume = {77}, year = {2019}, pages = {1221-1223}, abstract = {

A totally bio hardener acting with an unusual and new hardening mechanism derived from the exudate extract of the African trees Vachellia nilotica and Senegalia senegal was used to harden a maritime pine tannin resin without any aldehyde obtaining a completely bio adhesive for interior particleboard. For a density and pH given, the internal bond (IB) values increased simultaneously with the rate of bio-hardener. The optimal dry IB values (0.63 MPa) were obtained with 15\% of bio-hardener solids. The low IB value (0.38 MPa) was obtained with 6\% of bio-hardener solids. The IB of panels manufactured with UF as hardener are slightly higher than those using the above bio-hardeners.

}, author = {B. NDIWE and A. PIZZI and R. DANWE and B. TIBI and N. KONAI and S. AMIROU} } @article {1785, title = { Preparation and Evaluation of Glucose Based Non-Isocyanate Polyurethane Self-Blowing Rigid Foams }, journal = {POLYMERS}, volume = {11}, year = {2019}, abstract = {

A partially biobased self-blowing and self-hardening polyurethane foam from glucose-based non-isocyanate polyurethanes (g-NIPU) was prepared by reaction of glucose with dimethyl carbonate and hexamethylene diamine. However, these foam types generally require a high foaming temperature. In this paper, a self-blowing foam based on g-NIPU was prepared at room temperature by using maleic acid as an initiator and glutaraldehyde as a crosslinker. Water absorption, compression resistance, and fire resistance were tested. Scanning electron microscopy (SEM) was used to observe the foam cells structure. Middle infrared (ATR FT-MIR) and Matrix Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF) mass spectrometry were used to help to analyze the reactions during the foaming process. The results obtained showed that self- blowing rigid foams have good compression, this being directly proportional to the foam density. Increasing the amount of glutaraldehyde or reducing maleic acid thickens the cell walls and increases the density of the foams. MALDI-TOF analysis showed that g-NIPU reacts with both maleic acid and glutaraldehyde. The foams presented poor fire resistance indicating that, as for isocyanate based polyurethane foams, addition of a fire retardant would be necessary.

}, author = {X.D. XI and A. PIZZI and C. GERARDIN and H. LEI and X.Y. CHEN and S. AMIROU} } @article {1777, title = { Soy protein isolate-based polyamides as wood adhesives }, journal = { WOOD SCIENCE AND TECHNOLOGY }, volume = {54}, year = {2019}, pages = {89-102}, abstract = {

Soy protein isolate was reacted first with maleic anhydride and then hexamethylenediamine to synthesis soy protein isolate-based polyamides (SPIPA). Its bonding properties were measured by preparing laboratory three-layer plywood. Furthermore, a silane coupling agent (KH560), citric acid and maleic anhydride were added as cross-linkers to the SPIPA glue mix before hot pressing the panels. ATR FT-MIR and MALDI-ToF were used to determine the structures of the SPIPA, and thermomechanical analysis was used to analyze its thermomechanical properties. The results show that maleic anhydride reacts with amino acids in the soy protein molecule and then reacts with hexamethylenediamine to form carbamate-structured polyamides. This is confirmed by the ATR FT-MIR and MALDI-ToF results. Moreover, structural analysis indicates that a large number of branched structures are formed and occur in the SPIPA, rendering possible the formation of a network during curing, ensuring the bonding performance of the adhesive. The SPIPA adhesive presented good bonding strength and water resistance above the standard requirements of China National Standard GB/T 9846-2015. In particular, when maleic anhydride was added as a cross-linking agent, namely the SPIPA-MA adhesive, the panels\&$\#$39; dry and wet shear strengths were improved so that it can be considered as a suitable soy protein-based wood adhesive.

}, author = {X.D. XI and A. PIZZI and C. GERARDIN and X.Y. CHEN and S. AMIROU} } @article {1817, title = { Wheat protein hydrolysates-resorcinol-aldehydes as potential cold setting adhesives }, journal = { EUROPEAN JOURNAL OF WOOD AND WOOD PRODUCTS }, volume = {77}, year = {2019}, pages = {453-463}, abstract = {

Environmental concerns about natural adhesive materials are leading to an increasing interest towards the development of ecological products. The development of new value-added uses for wheat proteins led us to develop protein-based wood adhesives. Different protein cold-setting resins were formulated by reacting the protein hydrolysates with different aldehydes (formaldehyde, glyoxal and glutaraldehyde). Wood bonded with cold-setting protein adhesive with different aldehydes met the requirements for interior and exterior conditions, and the characterization was similar to those of conventional PRF (phenol-resorcinol-formaldehyde) adhesives. As the results indicate, both glyoxal and glutaraldehyde are able to react with wheat protein hydrolysates and are viable alternatives to formaldehyde and prospectively seem more environmentally friendly. Matrix-assisted laser desorption ionisation time-of-flight (MALDI-TOF) analysis allowed the identification of the main oligomer species obtained. The analysis showed that resin prepared with glutaraldehyde is not a simple mix of resorcinol-glutaraldehyde oligomers and amino acid, but a much more complex combination of various species including amino acid-glutaraldehyde and amino acid-resorcinol oligomers.

}, author = {S. AMIROU and A. PIZZI and X.D. XI} } @article {1767, title = { Melamine-Glyoxal-Glutaraldehyde Wood Panel Adhesives without Formaldehyde }, journal = {POLYMERS}, volume = {10}, year = {2018}, abstract = {

(MGG\&$\#$39;) resin adhesives for bonding wood panels were prepared by a single step procedure, namely reacting melamine with glyoxal and simultaneously with a much smaller proportion of glutaraldehyde. No formaldehyde was used. The inherent slow hardening of this resin was overcome by the addition of N-methyl-2-pyrrolidone hydrogen sulphate ionic liquid as the adhesive hardener in the glue mix. The plywood strength results obtained were comparable with those obtained with melamine-formaldehyde resins pressed under the same conditions. Matrix assisted laser desorption ionisation time of flight (MALDI ToF) and Fourier transform Infrared (FTIR) analysis allowed the identification of the main oligomer species obtained and of the different types of linkages formed, as well as to indicate the multifaceted role of the ionic liquid. These resins are proposed as a suitable substitute for equivalent formaldehyde-based resins.

}, author = {X.D. XI and A. PIZZI and S. AMIROU} } @article {1727, title = { Reactions with Wood Carbohydrates and Lignin of Citric Acid as a Bond Promoter of Wood Veneer Panels }, journal = { POLYMERS }, volume = {10}, year = {2018}, abstract = {

The reaction of citric acid with wood veneers was studied by Cross Polarization Magic Angle Spinning Nuclear Magnetic Resonance (CP MAS C-13 NMR) and matrix assisted laser desorption ionization time of flight (MALDI ToF) mass spectrometry. The analysis showed that reactions of citric acid occurred with both lignin and carbohydrate constituents of wood. The reactions occurring are esterifications between the carboxylic acid functions of citric acid and the numerous aromatic and aliphatic hydroxyl groups of the main wood constituents. Reaction of citric acid with glucose as a simple model compound of carbohydrates hydroxyl groups also yielded reactions leading to linear and branched oligomers by esterification. The result indicate that the reactions of esterification are accompanied in parallel by some internal rearrangements of lignin. The applied results on bonding wide flat wood surfaces such as veneers to obtain LVL panels yielded excellent strength results even if the conditions of pressing were more drastic than what is usual for this application. The applied bonding results have shown that citric acid has great potential to be used as a bio-binder for wood veneers.

}, author = {C. DEL-MENEZZI and S. AMIROU and A. PIZZI and X.D. XI and L. DELMOTTE} } @article {1677, title = { Citric acid as waterproofing additive in butt joints linear wood welding }, journal = { EUROPEAN JOURNAL OF WOOD AND WOOD PRODUCTS }, volume = {75}, year = {2017}, pages = {651-654}, abstract = {

Citric acid was used to improve resistance to water of the welded joint of spruce along the end-grain-to-end-grain faces. The use of 10-20\% citric acid as treatment during a very short time has been shown to markedly improve both the mechanical performance and the water resistance of welded spruce. Based on the results of the water resistance tests it appears that the application of citric acid as a natural waterproofing additive in wood welding is possible. The use of citric acid thus allows the preparation of welded wood joints satisfying the requirement of frequent short-term and long-term exposure to water. C-13 NMR analysis indicated that lignin modification of the welded material is related to the improvement of water resistance and shear properties of the welded joints.

}, author = {S. AMIROU and A. PIZZI and L. DELMOTTE} } @article {1703, title = { Optimization of Wood Welding Parameters for Australian Hardwood Species }, journal = { BIORESOURCES }, volume = {12}, year = {2017}, pages = {1007-1014}, abstract = {

Optimal linear wood welding parameters along the end-grain-to-end-grain faces were determined for Eucalyptus saligna, Eucalyptus pilularis, and Corymbia maculata. Joints made using Eucalyptus saligna showed a significant interaction between welding time ( WT), amplitude ( WA), and pressure ( WP). A preheating phase of 3 s at 0.4 MPa WP and 0.75 mm WA coupled with a WT of 2 s at 2.0 MPa WP and 1.5 mm WA provided the best shear strength results of 5.1 MPa. Joints made using Eucalyptus pilularis and Corymbia maculata snapped once the holding pressure was removed, suggesting that end-grain-to-end-grain welded fibers cannot withstand the thermal stresses generated when the surface to be welded is too small ( e. g., 13.5 cm(2)). However, grain orientation had a significant effect on the weld mechanical properties, as very strong edge-grain-to-edge-grain joints were produced with Eucalyptus pilularis and Corymbia maculata ( 9.5 and 6.2 MPa, respectively). The joints made of Eucalyptus saligna also showed significant improvement ( 7.3 MPa). Energy efficient combinations were usually those involving low WA and short WT, as WP had a marginal effect on energy consumption during the welding process.

}, author = {B. BELLEVILLE and S. AMIROU and A. PIZZI and B. OZARSKA} } @article {1694, title = { Water resistance of natural joint of spruce produced by linear friction welding without any treatment }, journal = { INTERNATIONAL WOOD PRODUCTS JOURNAL }, volume = {8}, year = {2017}, pages = {201-207}, abstract = {

This research work showed that spruce wood can be butt welded in a short time end-grain to-end-grain without any treatment. Wood welding has already been shown to be well adapted to the manufacture of wood structures of larger dimensions. When pressure increased, the welded material formed is of higher density and consequently the water resistance improved. The welded spruce samples present a much improved water resistance when the welding pressure was increased from 2.75 MPa to 3.75 MPa for the same welding time of 6 s. The welded interphase in end-grain-to-end-grain butt welding of spruce appears to occur by the formation of an interphase having the appearance of finger-joints. This is due to the different behaviours of the late and early wood rings of spruce during welding. This, by increasing the surface of contact, is shown to improve the water resistance of the original butt joint.

}, author = {S. AMIROU and A. PIZZI and B. BELLEVILLE and L. DELMOTTE} } @article {1586, title = { Hyperbranched Poly(amidoamine)s as Additives for Urea Formaldehyde Resin and Their Application in Particleboard Fabrication }, journal = { BIORESOURCES }, volume = {10}, year = {2015}, pages = {782-792}, abstract = {

Three types of hyperbranched poly(amidoamine)s (PAMAMs), namely HB(MA-EDA)1, HB(MA-EDA)3, and HB(MA-DETA)1.2, were synthesized and used as modifiers for urea-formaldehyde (UF) resin. Particleboards bonded with these modified UF resins were fabricated and evaluated. The results showed that these PAMAMs caused some adverse effects on UF resin performance. The main problems of PAMAMs were their high buffer capacity and high pH values, which are attributed to the peripheral amino groups at the terminals, both of which had a serious negative influence on UF resin curing. These findings were supported by the gel time measurements in parallel with a predictive investigation on the resins using thermomechanical analysis (TMA). The gel time was prolonged, and the maximum modulus of elasticity (MOE) values decreased with the addition of HB(MA-EDA)3. The use of a strong acid curing agent (HCOOH) could reduce the gel time into a normal range; however the performance of the corresponding particleboards still deteriorated. Therefore, these PAMAMs are considered not suitable for the modification of UF resin when applied as final additives. Beyond all expectations, the modified UF resin that employed very finite amounts of HB(MA-EDA)1 as a pH regulator instead of NaOH yielded a considerable upgrade in performance of the produced particleboards.

}, url = {https://hal.archives-ouvertes.fr/hal-01598426/}, author = {J.Z. ZHANG and S. AMIROU and H.A. ESSAWY and A. PIZZI and Q. GAO and J.Z. LI} } @article {1391, title = {Utilisation of hydrophilic/ hydrophobic poly(amidoamine)s as additives for melamine-urea-formaldehyde (MUF) adhesives and consequent application in particleboard fabrication,}, journal = {Polymers Adv. Technol. }, year = {2015}, pages = { 2255-2264 }, author = {S. AMIROU and J. ZHANG and H. ESSAWY and A. PIZZI and A. ZERIZER and L. DELMOTTE} } @article {1198, title = {Effect of some hyperbranched poly(amidoamine)s as additives for urea formaldehyde (UF) resin before their application in particleboards fabrication. }, journal = {BioRessources}, volume = {10}, year = {2014}, month = {2014}, chapter = {782}, author = {J. ZHANG and S. AMIROU and A. PIZZI and Q. GAO and H. ESSAWY and J. LI} } @article {1162, title = {Investigation of chemical, physical, and mechanical properties of Algerian date palm wood. }, journal = {Materials Testing}, volume = {56}, year = {2014}, month = {2014}, chapter = {236}, author = {S. AMIROU and A. ZERIZER and A. PIZZI} } @article {1179, title = {Utilization of hydrophilic/hydrophobic Hyperbranched Poly(amidoamines)s additives fort melamine urea formaldehyde (MUF) adhesives.}, journal = {Polymer Composites}, year = {2014}, month = {2014}, author = {S. AMIROU and J. ZHANG and A. PIZZI and H. ESSAWY and A. ZERIZER and J. LI and L. DELMOTTE} } @article {608, title = {Effects of corona discharge treatment on the mechanical properties of biocomposites from polylactic acid and Algerian date palm fibres}, journal = {Sci. Res. Essays}, volume = {8}, year = {2013}, month = {2013}, chapter = {946-952}, author = {S. AMIROU and A. ZERIZER and I. HADDADOU and A. MERLIN} } @article {682, title = {Particleboard production from date palm biomass}, journal = {European Journal of Wood and Wood Products}, volume = {71}, year = {2013}, month = {2013}, chapter = {717-723}, author = {S. AMIROU and A. ZERIZER and A. PIZZI and I. HADDADOU and X. ZHOU} }