Saad Nader^1,2, Felipe Guzman³, Raphael Becar¹, César Segovia⁴, Cecilia Fuentealba³, Miguel Peirera³, Evelyne Mauret², Nicolas Brosse^1,*

Journal of Renewable Materials, Vol.10, No.2, pp. 263-271, 2022, DOI:10.32604/jrm.2022.017923

Abstract The reinforcing impact of Lignocellulosic micro and nanofibrillated cellulose (L-MNFCs) obtained from Eucalyptus Globulus bark in Urea-Formaldehyde UF adhesive was tested. L-MNFCs were prepared by an environmentally friendly, low-cost process using a combination process involving steam explosion followed by refining and ultra-fine grinding. Obtained L-MNFCs showed a web-like morphology with some aggregates and lignin nanodroplets. They present a mixture of residual fibers and fine elements with a width varying between 5 nm to 20 μm, respectively. The effects of the addition of low amounts of L-MNFCs (1% wt.) on the properties of three different adhesives (Urea-Formaldehyde UF, Phenol-Formaldehyde PF, and Tannin-Hexamine TH)… More > Graphic Abstract

Xinyi Chen^1,2, Antonio Pizzi^1,*, Xuedong Xi^1,2, Xiaojian Zhou², Emmanuel Fredon¹, Christine Gerardin³

Journal of Renewable Materials, Vol.9, No.6, pp. 1045-1057, 2021, DOI:10.32604/jrm.2021.015066

Abstract Soy-protein isolate (SPI) was used to prepare non-isocyanate polyurethane (NIPU) thermosetting adhesives for wood panels by reacting it with dimethyl carbonate (DMC) and hexamethylene diamine. Both linear as well as branched oligomers were obtained and identified, indicating how such oligomer structures could further cross-link to form a hardened network. Unusual structures were observed, namely carbamic acid-derived urethane linkages coupled with lactam structures. The curing of the adhesive was followed by thermomechanical analysis (TMA). It appeared to follow a two stages process: First, at a lower temperature (maximum 130°C), the growth of linear oligomers occurred, finally forming a physically entangled network.… More >