Document Type : Research Paper

Authors

1 Assistant Prof., Wood and Forest Products Science Research Division, Research institute of forests and rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran

2 LERMAB, Faculte des Sciences, University of Lorraine, Blvd. des Aiguillettes, 54000 Nancy, France

3 Assistant Prof., Wood and Forest Products Science Research Division, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO) P.O. Box 13185-116, Tehran, Iran

Abstract

Presently, because of the human health issues related to the formaldehyde gas emission initiated from traditional wood adhesives like urea formaldehyde, the bio-sbased adhesives has shown a good solution for preventing health hazards for human and the environment. To achieve an acceptable approach in wood based composites production, these adhesive need to qualify different standard limitations. This research was conducted to improve the bio-based soy-tannin adhesive for producing plywood with acceptable properties. For this goal, different adhesive formulations were prepared in the laboratory and they were treated at different temperature (40, 60, 80 ºC). Poplar wood plies with 2 mm nominal thickness were used to produce plywood specimens. The results showed the effectiveness of adhesives with heat pre-treatments at different temperature on shear strength (dry and wet) of plywood specimens. The highest shear strength of plywood specimens was achieved for 40 ºC treated adhesive in both dry and wet condition. Based on the results of shear strength test, all manufactured plywood specimens successfully met EN-314-2 standards requirement. Also, the results of delamination test revealed that plywood specimens which prepared by 40 ºC treated adhesive can successfully use for indoor condition, based on ANSI-HPV-1 requirements.

Keywords

-Amaral-Labat, G.A., Pizzi, A., Goncalves, A.R., Celzard, A., Rigolet, S. and Rocha, G.J.M., 2008. Environment-friendly soy flour-based resins without formaldehyde. Journal of Applied Polymer Science, 108: 624–632.
-Food and Agriculture Organization (FAO) annual report, United Nations, 2017.
-Ghahri, S., Bari, E. and Pizzi, A., 2021. The Challenge of environment-friendly adhesives for bio-composites. In: Jawaid M., Khan T.A., Nasir M., Asim M. (eds) Eco-Friendly Adhesives for Wood and Natural Fiber Composites. Composites Science and Technology. Springer, Singapore. https://doi.org/10.1007/978-981-33-4749-6_11
-Ghahri, S., Chen, X., Pizzi, A., Hajihassani, R. and Papadopoulos, A.N., 2021. Natural tannins as new cross-linking materials for soy-based adhesives. Polymers, 13: 4. 595-610.
-Ghahri, S. and Hajihassani, R., 2021. Possibility of replacing urea formaldehyde resin by soy adhesive in plywood production. Journal of Wood & Forest Science and Technology, 28: 3. 131-142.
-Ghahri, S., Mohebby, B., Pizzi, A., Mirshokraie, A. and Mansouri, H.M., 2018. Improving water resistance of soy-based adhesive by vegetable tannin. Journal of Polymers and the Environment, 26: 1881-1890.
-Ghahri, S. and Pizzi A., 2018. Improving soy-based adhesives for wood particleboard by tannins addition. Wood Science and Technology, 52: 261-279.
-Ghahri, S., Pizzi, A., Mohebby, B., Mirshokraie, A. and Mansouri, H.M., 2018. Soy-based, tannin-modified plywood adhesives. Journal of Adhesion, 94, 218–237.
-Pizzi, A., 2016. Wood products and green chemistry. Annals of Forest Science, 73:185–203.
-Steele P.H., Kreibich R.E., Steynberg P.J. and Hemingway R.W., 1998. Finger jointing green southern yellow pine with a soy-based adhesive. Adhesive Age, 50: 1. 49–54.
-Taghiyari, H.R., Hosseini, B., Ghahri, S., Ghofrani, M. and Papadopoulos, A.N., 2020. Formaldehyde emission in micron-sized wollastonite-treated plywood bonded with soy flour and urea-formaldehyde resin. Applied Sciences, 10, 6709.
-Wescott J.M. and Frihart C.R., 2004. Competitive soybean flour/ phenol-formaldehyde adhesives for oriented strand board, 38th InternationalWood Composites Symposium Proceedings, August 6 – 8, 2004: 312-321. doi:10.3390/app10196709.