Effect of Nano cellulose reinforced adhesive on the strength and stiffness of wooden joints

Gourav Kamboj

Disertační práce

Abstract:

Adhesives play an essential role in the wood industry. The performance of existing wood joints is highly dependent on the performance of the wood species, geometry type, and type of adhesive. Polyvinyl acetate (PVAc) and polyurathene (PUR) are predominantly used in furniture as well as structural applications. In this study, two types of adhesive (PVAc and 1C-PUR) were used in wood joints (dowel, finger, dovetail, and lap joints). The joint performance improvement was investigated by adding nanocellulose. Nanocellulose (cellulose nanofiber and cellulose nanocrystals) is of natural origin and possesses remarkable mechanical properties. However, dispersion on nanocellulose in adhesive, especially in PUR, has been a challenging. To overcome this difficulty, chemical modification (acetylation) of nanocelluose was also attempted. The performance of the nanocelluose reinforced adhesives (PVAc and PUR) was assessed with a lap shear test. A study with a scanning electron microscope (SEM) was carried out to assess the bondline. The effect of cyclic moisture (8-19%) exposure on the performance of the nanocellulose reinforced adhesive bond was also assessed. The optimum value of elastic stiffness and shear strength was obtained with the addition of 1% nanocellulose. The resulting mechanical properties of lap shear joints were investigated and the difference between the pure adhesive and nanocellulose reinforced adhesive were discussed.

Keywords

Wood joints, Nanocellulose, Polyvinyl acetate (PVAc), Polyurethane (1C-PUR), Mechanical characteristics

Jazyk práce: angličtina

Datum vytvoření / odevzdání či podání práce: 20. 5. 2022

Obhajoba závěrečné práce

• Vedoucí: doc. Ing. Milan Gaff, PhD.
• Oponent: Rastislav Lagaňa, Ing., externi, Jozef Ráheľ, externi

Česká zemědělská univerzita v Praze

Fakulta lesnická a dřevařská

Doktorský studijní program / obor:
Forestry Engineering / Wood Processing and Forest Machinery