Bengang Zhang^1,*, Antonio Pizzi^2,*, Mathieu Petrissans¹, Anelie Petrissans¹, Colin Baptiste¹

Journal of Renewable Materials, Vol.11, No.12, pp. 4097-4121, 2023, DOI:10.32604/jrm.2023.029761

Abstract Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many, if not all of the tannin hydroxyl groups with –NH₂ groups. A tannin-aminated tannin (ATT) particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-liking the two by substituting tannin’s hydroxyl groups with the –NH₂ groups on the aminated tannin to form –NH-bridges between the two. The resulting particleboard coating gave encouraging results when pressed at 180°C for 3 min. Conversely, the system in which tannin was reacted/cross-liked with urea (ATU) by a similar amination reaction… More >

Elham Azadeh¹, Ummi Hani Abdullah^2,3, Christine Gerardin^1,*, Antonio Pizzi^1,*, Philippe Gerardin¹, Cesar Segovia⁴

Journal of Renewable Materials, Vol.11, No.10, pp. 3625-3645, 2023, DOI:10.32604/jrm.2023.030373

Abstract Water repellant, flexible biofoams using tannin esterified with various fatty acid chains, namely lauric, palmitic and oleic acids, by reaction with lauryl chloride, palmitoyl chloride, and oleyl chloride were developed and their characteristics compared with the equivalently esterified rigid biofoams. Glycerol, while initially added to control the reaction temperature, was used as a plasticizer yielding flexible biofoams presenting the same water repellant character that the equivalent rigid foams. Acetaldehyde was used as the cross-linking agent instead of formaldehyde, as it showed a better performance with the esterified tannin. The compression results showed a significant decrease of the Modulus of Elasticity… More >