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together, leaving the center layer perpendicular to allow greater stability and strength, making them an alternative to solid wood in many applications [2]. The main adhesive widely used in OSB panel manufacture is phenol formaldehyde (PF), the second most important wood composite adhesive, which is of an exterior grade. Nevertheless, PF has the defect of having a slow curing time, and it requires higher temperatures than urea formaldehyde adhesives [3]. Another important disadvantage is that these formaldehyde-based adhesives emit gases that are potentially harmful to human health, causing, for example, throat and nose cancer [4]. The emissions of formaldehyde- type gases, which are toxic to humans, are present in most of the commercial adhesives used in OSB manufacture or other wood-based panels. This is why different alternatives used for the production of different types of boards in the construction and furniture industry by American and European markets have undergone great development, which is reflected in the demanding regulations regarding the maximum emission of volatile organic compounds (VOCs) allowed for market products, while in South America, there is a low level of innovation both in terms of production techniques and in the development of different bio-based adhesives for the manufacture of boards. This creates an opportunity to develop boards in compliance with the most demanding regulations worldwide, with the possibility of placing a product in this market by taking advantage of the abundant natural resources available in Chile. Green or bio-based adhesives were used in the 1970s before being replaced by PF ad- hesives due to the greater bond durability provided by such adhesives. The most common bio-based adhesives are protein-based adhesives, such as bone, animal skin, blood, and soy. Protein-based adhesives are not useful when one is working with high moisture levels. However, the most important factor is their environmental benefit, although improvements in the performance and production cost of synthetic resins had not been achieved until 2004, when Li et al. developed adhesives based on soybean flour and combined them with other adhesives [5,6]. When soybean flour becomes part of the adhesive network instead of being used only as a filler, it can replace approximately half of the phenol in formulations, meeting the performance requirements of commercial OSB adhesives [7]. Green adhesives can also be derived from wood components like tannin and lignin. Tannins, though highly reactive and usable as partial phenol substitutes, are costly and limited in availability, with issues such as high viscosity and inconsistent reactivity. Lignin, a low-cost byproduct of papermaking, is less reactive but more abundant. Modified forms like lignosulfonates show promise, and advances in biorefinery technology may enhance lignin’s reactivity, increasing its potential as a sustainable adhesive component [6,8,9]. Several researchers have been studying green adhesives to partially or completely replace formaldehyde-based adhesives; the latest investigations about this are the following ones. Sugahara et al. [10], in 2025, investigated the feasibility of using fast-growing euca- lyptus wood and castor oil polyurethane adhesive to produce OSB panels and evaluated their physical and mechanical properties. Strikun et al. [11], in 2024, manufactured envi- ronmentally friendly thermal insulation panels made of pine wood fibers with a bio-based adhesive and determined their relevant technical properties. During the same year, 2024, Siahkamari [12] developed a lignin-based phenolic adhesive for engineered wood products, studying the potential of lignin and glyoxal as sustainable replacements for phenol and formaldehyde. In 2024, Widyorini et al. [13] analyzed the properties of eco-friendly oriented strand board produced from oil palm trunks in which natural adhesives made from sucrose and ammonium dihydrogen were incorporated. In 2023, Núñez-Decap et al. [14] manu- factured a bio-based wood adhesive from yeast protein, probed its efficiency regarding physical–mechanical properties, and conducted an evaluation of the formaldehyde emis- sions of particleboard. In 2022, Asafu-Adjaye et al. [15] investigated the use of fast pyrolysis
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