Properties and potential use of Irvingia gabonensis and Irvingia wombolu kernel extracts as natural wood adhesives: Towards formaldehyde free wood composite products

IRG/WP 18-40832

A O Alawode, S O Amiandamhen, M Meincken, L Tyhoda

Irvingia species are widely distributed in central and West Africa as well as parts of Asia and are earmarked for domestication due to the multitude of potential products that can be obtained from them. With renewed interest in renewable sources, the current study establishes the feasibility of utilizing extracts from Irvingia gabonensis and Irvingia wombolu kernels as wood adhesives. Proximate analysis of the kernels was carried out and chemical analysis of I. wombolu kernels revealed the following composition: carbohydrates (21.2%), protein (6.5%), fat (67.5%), ash (2.3%) and moisture (2.5%). I. gabonensis kernels had the following composition: carbohydrates (16.8%), protein (7.97%), fat (70.5), ash (2.4%) and moisture (2.3%). Three extraction methods were compared in terms of efficiency, yield and adhesive properties, i.e. water with no catalyst, as well as sodium chloride, and sodium metabisulphite. The results showed that there was no significant difference in the yields from different extraction methods and species; and therefore a simple water extraction without catalyst was adequate. The adhesives were applied on glass fibre paper strips, the tensile strength of the paper strips was evaluated. The results showed that adhesives produced using water extraction process had the highest tensile strength and elastic modulus for both species, with values of 14700 and 13600 N/m-g; and 46.7 and 44.1 GPa respectively. A comparison of strength properties was made with a commercial formaldehyde-based adhesive, Bondtite®. The results revealed that the tensile strength of Bondtite® is about 17.6% higher than the highest strength of the Irvingia adhesive. The study concluded that Irvingia adhesive is a promising non-formaldehyde adhesive that can be used in wood composite applications.

Keywords: formaldehyde free adhesive, Irvingia gabonensis, Irvingia wombolu, natural adhesive

Conference: 18-04-29/05-03 Johannesburg, South Africa

Download document (232 kb)
free for the members of IRG.

Order document from secretariat