## 3 Results and Discussion
### Physicochemical and Electrical Properties of PVAc-Bioadditive IFR Adhesive Blends  
Table 6 shows the average values of the physicochemical and electrical properties of the modified commercial PVAc adhesive, using the two formulations of the IFR bioadditive, F1 and F2.  
It was observed that by increasing the concentration of the IFR bioadditive formulations in the PVAc adhesive blends, there was a progressive increase in pH and a decrease in electrical conductivity. This effect was more pronounced in the adhesive blends with F2 formulation, which contains a higher proportion of Mg(OH)2, which increased alkalinity and reduced electrical conductivity. Mg(OH)2 is an electrical insulator, with a band gap of 5.7 eV [68], which contributes to this decrease in electrical conductivity, as has also been observed in other Mg(OH)2-modified materials [69]. On the other hand, as was mentioned by [PERSON] et al. [1], electrical conductivity is a relevant property, because most of the time wood products bonded with PVAc adhesive are pressed using radiofrequency technology, which accelerates cured and production times [70,71]. So, the idea of measuring this property is to observe how this parameter of the bioadditive could influence the electrical conductivity of the modified adhesive. It was observed that the viscosity of the adhesive blends decreased when incorporating the IFR bioadditive, but when exceeding 10% concentration, the viscosity approached that of the pure PVAc adhesive, especially in the F2 formulation. This decrease is attributed to an inefficient interaction between PVAc and the bioadditive [72], reducing the viscosity at low concentrations. On the other hand, an increase in viscosity upon exceeding 10% bioadditive suggests an increased macromolecular interaction, due to the higher availability of the bioadditive in the system, forming bonds such as \"Van der Waals forces\" [73] and \"hydrogen bridges\" [74,75] between the adhesive and the IFR bioadditive, which increases fluid friction and thus viscosity. Finally, the density values of the adhesive blends were close to 1 g/cm3, without significant variations. As expected, the solids content increased as the concentration of the bioadditive increased, since the blend of the adhesive with the bioadditive incorporated additional  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**PVAc-Bioadditive IFR** & **pH** & **Viscosity (cP)** & **Density (g/cm3)** & **Solids Content (\%)** & **Electrical Conductivity (mS)** \\ \hline PVAc & 3.26 & 5823.33 & 1.12 & 53 & 13.22 \\ \hline PVAc-2.5\% F1 & 3.35 & 3217.67 & 1.11 & 53 & 12.26 \\ \hline PVAc-5\% F1 & 3.56 & 3243.33 & 1.01 & 54 & 12.19 \\ \hline PVAc-7.5\% F1 & 3.83 & 3237.67 & 1.08 & 55 & 12.16 \\ \hline PVAc-10\% F1 & 4.25 & 5493.33 & 0.97 & 55 & 11.78 \\ \hline PVAc-12.5\% F1 & 4.89 & 5740.00 & 0.99 & 56 & 11.30 \\ \hline PVAc-2.5\% F2 & 3.52 & 3868.67 & 1.12 & 53 & 12.98 \\ \hline PVAc-5\% F2 & 3.88 & 4320.00 & 1.01 & 54 & 12.73 \\ \hline PVAc-7.5\% F2 & 4.40 & 3311.00 & 0.99 & 54 & 11.69 \\ \hline PVAc-10\% F2 & 4.74 & 6616.67 & 0.99 & 54 & 11.63 \\ \hline PVAc-12.5\% F2 & 6.67 & 8106.67 & 1.04 & 56 & 11.17 \\ \hline \hline \end{tabular}
\end{table}
Table 6: Physicochemical and electrical properties of the PVAc-bioadditive IFR adhesive blends.  
solid elements. The variation in solids content was similar for adhesive blends containing F1 and F2 formulations.  
Adhesive Bond Line Quality on Wood Specimens Glued with PVAc-Bioadditive IFR Adhesive Blends: Mechanical Properties