## 3 Results and Discussion
### Bending Strength of the L-type Corner Joints Made of the Fabricated Eco-friendly Composites  
The results of the bending strength are given in Table 2 and the boxplot graphic in Figure 5. The performance of the joints made of the eco-friendly composites with a Minifix connector was unsatisfactory. In practice, they cannot be used as connecting elements due to the fact that the bolt of Minifix reacts with a limited part of the panel and the pullout strength of this part of the connector is significantly less. The rest of the tested joints showed sufficient bending capacity. The highest bending capacity was demonstrated by the joints with \(8\times 30\) mm dowels (8.02 N\(\cdot\)m), followed by the Confirmat \(\omega 7\times 50\) mm (6.95 N\(\cdot\)m) and screws for wood \(\omega 3.5\times 50\) mm (4.94 N\(\cdot\)m). According to [PERSON]'s test, a significant difference was observed only between the screw joints and the group of dowels and the Confirmat joints. The low strength of the joint with wood screws was due to the inhomogeneity of the eco-friendly panels fabricated from residual wood fibres. In contrast, the corner joints made from MDF panels exhibited an almost equal strength to the joints with the Confirmat and screws due to the homogeneity of the panels. This is proof that the small diameter of the screws had an adverse effect on the strength of the joint. Dowel joints constructed from eco-friendly composites showed almost 2.5 times lower bending capacity compared with the same joints made from MDF panels, while the joints with the Confirmat had a difference of 5 times and the joint with screws had a difference of 6.5 times. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Panel No.**} & **Density \(\rho\),** & **Water** & **Thickness** & **Bending** & **Modulus of** & **Internal** \\  & **(kg\(\cdot\)m\({}^{-3}\))** & **Absorption** & **Swelling (24 h) \(G\), (\%)** & **Swelling (24 h) \(G\), (\%)** & **Strength (MOR) \(fm\), (\(\mathbf{MOE}\))** & **Bond** \\  & & **(24 h) \(A\), (\%)** & **h) \(G\), (\%)** & **(N\(\cdot\)mm\({}^{-2}\))** & **(N\(\cdot\)mm\({}^{-2}\))** & **Strength (\(\mathbf{f_{r}}\)** \\ \hline
1 & 772 \(\pm\) 8.72 & 150.97 \(\pm\) 4.87 & 76.74 \(\pm\) 2.81 & 17.0 \(\pm\) 0.67 & 1990 \(\pm\) 53 & 0.14 \(\pm\) 0.03 \\
2 & 736 \(\pm\) 9.71 & 175.52 \(\pm\) 4.25 & 78.24 \(\pm\) 2.35 & 18.9 \(\pm\) 0.76 & 2260 \(\pm\) 61 & 0.12 \(\pm\) 0.01 \\
3 & 681 \(\pm\) 6.78 & 184.36 \(\pm\) 5.73 & 83.63 \(\pm\) 2.76 & 20.6 \(\pm\) 1.32 & 2450 \(\pm\) 72 & 0.14 \(\pm\) 0.02 \\
4 & 757 \(\pm\) 10.12 & 144.65 \(\pm\) 5.91 & 83.63 \(\pm\) 2.95 & 17.0 \(\pm\) 1.49 & 1930 \(\pm\) 49 & 0.14 \(\pm\) 0.02 \\
5 & 743 \(\pm\) 9.36 & 180.06 \(\pm\) 4.74 & 89.08 \(\pm\) 3.03 & 20.6 \(\pm\) 0.93 & 2280 \(\pm\) 67 & 0.12 \(\pm\) 0.01 \\
6 & 751 \(\pm\) 6.92 & 163.36 \(\pm\) 6.01 & 94.08 \(\pm\) 3.12 & 16.6 \(\pm\) 1.37 & 2180 \(\pm\) 56 & 0.14 \(\pm\) 0.02 \\
7 & 737 \(\pm\) 8.53 & 178.99 \(\pm\) 5.38 & 75.58 \(\pm\) 2.24 & 17.8 \(\pm\) 1.52 & 2320 \(\pm\) 42 & 0.15 \(\pm\) 0.03 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Mechanical and physical properties of the composites produced (MOR: modulus of rupture). From the statistical analysis of the one-way ANOVA test and the pairwise comparison performed with the Tukey HSD test, a significant difference of \(\alpha=0.05\) at a confidence level of 95% was found in four groups between the obtained bending strength of the L-type end corner joints constructed from eco-friendly composites and MDF panels. The groups are presented in Table 3. All joints made of the eco-friendly composites fell in group \"D,\" together with Rafix in MDF. The dowel joints in the eco-friendly composites were in one group with Minifix in MDF.