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emitted the lowest amount (0.005 ppm), while the OSB-1 sample emitted the highest (0.007 ppm), with differences that are also not significant. It can be said that the OSB panels manufactured with GA presented formaldehyde emissions as low as those manufactured with PF adhesive, which was expected because, in general, phenol-formaldehyde adhesive corresponds to the formaldehyde-based adhesive that discharges the lowest amount of formaldehyde compared to other formaldehyde-based adhesives like urea-formaldehyde (UF), due to PF resins tending to be more chemically stable and less susceptible to hydrolysis than UF resins [47]. On the other hand, the results obtained are so low that they almost correspond to the formaldehyde naturally emitted by the wood itself. For example, radiata pine wood discharges approximately 0.05 ppm of formaldehyde [48]. In any case, the formaldehyde emissions of the three evaluated samples meet the requirement of the UNE-EN 18,986 [33] standard (formaldehyde emission require- ment ≤ 0.101 ppm) and could be classified as class E1. Furthermore, Commission Reg- ulation (EU) 2023/1464 [49] has proposed a requirement of 0.05 ppm for formaldehyde emissions in furniture and wood-based articles, which will be effective in 2026. 4. Conclusions OSB panels manufactured with green adhesives were up to 46% less susceptible to color change after UV exposure and presented statistically the same dimensional stability under water immersion as an OSB panel manufactured with phenol-formaldehyde adhesive. In terms of mechanical properties, the OSB-1 sample outperformed the control sample by 7% (MOE in flatwise), 13% (MOR in edgewise), and reached 68% (tensile strength), 85% (internal bond strength), and 87% (Janka hardness) of the control sample. In most cases, the OSB samples manufactured with green adhesives presented statistically the same performance as the OSB samples manufactured with PF adhesive. Furthermore, all the OSB samples tested could be classified as OSB/2, E1. The phenol-formaldehyde adhesives could be easily substituted by green adhesives in the manufacturing of OSB panels, considering the fabrication parameters, and physical, mechanical, and thermal properties, since they evidenced, in most cases, statistically equal results to the control OSB panel. Author Contributions: Conceptualization, M.N.-D., F.D.-S. and C.O.-C.; methodology, M.N.-D., F.D.-S., B.M.-R. and V.H.-C.; software, M.N.-D. and C.O.-C.; validation, M.N.-D., F.D.-S., C.O.-C. and M.V.-V.; formal analysis, M.N.-D., F.D.-S., C.O.-C., B.M.-R. and M.V.-V.; investigation, M.N.-D., F.D.-S., C.O.-C., B.M.-R. and M.V.-V.; resources, M.N.-D. and F.D.-S.; data curation, M.N.-D., F.D.-S. and C.O.-C.; writing—original draft preparation, M.N.-D. and C.O.-C.; writing—review and edit- ing, M.N.-D. and C.O.-C.; visualization, M.N.-D.; supervision, M.N.-D.; project administration, M.N.-D.; funding acquisition, M.N.-D. All authors have read and agreed to the published version of the manuscript. Funding: This research received no external funding; nevertheless, the APC was funded by Centro Nacional de Excelencia para la Industria de la Madera (CENAMAD)—ANID BASAL FB210015. Data Availability Statement: The data are unavailable due to privacy restrictions associated with an ongoing investigation project. Acknowledgments: We extend our gratitude to the Wood and Adhesive Engineering Products Labora- tory (PRODIMA-LAB) of the Department of Civil and Environmental Engineering at the Universidad del Bío-Bío for their collaboration, as well as the equipment and infrastructure they provided. Conflicts of Interest: The authors declare no conflicts of interest.
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