International audienceContext Condensed tannins have been successfully used as substitutes for phenol in the production of resins for wood products. However, the enhancement of the properties of tannin-based resins with nontoxic and cost effective additives is of great interest.• Methods In the present work, the performance enhancement of tannin-based particleboards with cellulose nanofibers was investigated.• Results In presence of 2 % of cellulose nanofibers, the viscosity of tannin-based adhesives and the internal bonding strength (IB) of the corresponding particleboards were increased from 350 to 5,462 mPa·s and from 0.85 to 0.98 MPa respectively. The modulus of elastic (MOE) and modulus of rupture (MOR) of the resins were also notably increased while thickness swelling (TS) of the panels was not affected.• Conclusion The addition of cellulose nanofibers to tannin adhesives is an effective method for the production of high performance particleboards. Tannin-based adhesive containing 2 % of cellulose nanofibers exhibits the best mechanical strength.Key messageThe addition of cellulose nanofibers into tannin-based adhesives notably enhanced the mechanical properties of the wood particleboards produced. The formulation containing 2 % (w/w) of cellulose nanofibers exhibited the best mechanical strength
In this study, cellulose nanofibrils (CNFs) were successfully isolated from coconut palm petiole residues falling off naturally with chemical pretreatments and mechanical treatments by a grinder and a homogenizor. FTIR spectra analysis showed that most of hemicellulose and lignin were removed from the fiber after chemical pretreatments. The compositions of CNFS indicated that high purity of nanofibrils with cellulose contain more than 95% was obtained. X-ray diffractogram demonstrated that chemical pretreatments significantly increased the crystallinity of CNFs from 38.00% to 70.36%; however, 10-15 times of grinding operation followed by homogenizing treatment after the chemical pretreatments did not significantly improve the crystallinity of CNFs. On the contrary, further grinding operation could destroy crystalline regions of the cellulose. SEM image indicated that high quality of CNFs could be isolated from coconut palm petiole residues with chemical treatments in combination of 15 times of grinding followed by 10 times of homogenization and the aspect ratio of the obtained CNFs ranged from 320 to 640. The result of TGA-DTG revealed that the chemical-mechanical treatments improved thermal stability of fiber samples, and the CNFs with 15 grinding passing times had the best thermal stability. This work suggests that the CNFs can be successfully extracted from coconut palm petiole residues and it may be a potential feedstock for nanofiber reinforced composites due to its high aspect ratio and crystallinity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.