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The densities obtained for each OSB sample ranged between 705 and 822 kg/m 3 , with the OSB-1 sample reaching 86% of the density of the control sample, while the OSB-2 sample showed statistically the same density as the OSB-C sample. The moisture content results for the OSB samples ranged between 2% and 5%. The OSB-C and OSB-1 samples presented the same value, while the OSB-2 sample showed an increase of approximately 150% compared to the other samples. However, all values remained within the expected range (2–6%). The thickness swelling results after 24 h ranged between 31.22% and 32.07%, while the results after 48 h ranged between 33.31% and 33.97%. This physical property showed no significant differences between the samples tested (OSB produced with green adhesives and those with phenol-formaldehyde adhesive), nor between the two immersion durations. This indicates that the OSB samples produced with green adhesives exhibited the same dimensional stability under water immersion as the control sample manufactured with a formaldehyde-based adhesive. 3.3. Mechanical Properties The results for the stiffness property (MOE) of the different samples subjected to the bending test in the flatwise position are presented in Figure 3 and ranged from 3646 MPa (OSB-2) to 5675 MPa (OSB-1). The OSB-1 sample showed the highest stiffness but did not present statistically significant differences compared to the control sample (OSB-C). On the other hand, the OSB-2 sample reached 68.71% of the stiffness measured in the control sample and showed significant statistical differences compared to both OSB-C and OSB-1. In the edgewise position, the results ranged from 3051 MPa (OSB-C) to 3666 MPa (OSB-2), with the OSB-1 and OSB-2 samples outperforming the control sample by 17.86% and 20.15%, respectively. Nevertheless, no statistically significant differences were observed among the three tested samples. The results for the strength property (MOR) of the different samples subjected to the bending test in the flatwise position are also presented in Figure 3 and ranged from 23.44 MPa (OSB-2) to 45.11 MPa (OSB-C). The OSB-1 and OSB-2 samples reached 94.35% and 51.96%, respectively, of the strength measured in the control sample OSB-C. Although no statistically significant differences were found between the OSB-1 and OSB-C samples, significant differences were observed between OSB-2 and both OSB-1 and OSB-C. In the edgewise position, the results ranged from 23.79 MPa (OSB-C) to 26.97 MPa (OSB-1), with the OSB-1 and OSB-2 samples outperforming the control sample by 13.37% and 5.97%, respectively. Nevertheless, no statistically significant differences were observed among the tested samples. In general, the results revealed that the samples of OSB-1 in a flatwise position and both OSB-1 and OSB-2 samples in an edgewise position exhibited the same behavior as the control sample manufactured with phenol-formaldehyde adhesive. These results are consistent with those of Bandara and Wu, 2018 [19], who also obtained similar MOE and MOR values when comparing OSB panels manufactured with a PF adhesive against LPF modified with different percentages of canola protein with ammonium. From the bending test, it was also possible to obtain load–displacement curves for the flatwise and edgewise positions of each sample (Figure 4), as well as the resulting modes of failure (Figure 5). Figure 4 shows that the OSB samples in the flatwise position exhibited stiffer performance and reached higher loads than the those in the edgewise position, especially OSB-C and OSB-1. This explains why OSB panels are primarily used in flatwise applications, where their vertical density profile, high face densities and low core density are advantageous; higher face stiffness enhances flexural behavior [38].
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