Structural Application of Eco-Friendly Composites from Recycled Wood Fibres Bonded with Magnesium Lignosulfonate
Abstract
:1. Introduction
2. Materials and Methods
3. Results and Discussion
3.1. Formaldehyde Content
3.2. Mechanical and Physical Properties
3.3. Bending Strength of the L-type Corner Joints Made of the Fabricated Eco-friendly Composites
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Panel No. | Density ρ, (kg·m−3) | Water Absorption (24 h) A, (%) | Thickness Swelling (24 h) Gt, (%) | Bending Strength (MOR) fm, (N·mm−2) | Modulus of Elasticity (MOE) Em, (N·mm−2) | Internal Bond Strength ft, (N·mm−2) |
---|---|---|---|---|---|---|
1 | 772 ± 8.72 | 150.97 ± 4.87 | 76.74 ± 2.81 | 17.0 ± 0.67 | 1990 ± 53 | 0.14 ± 0.03 |
2 | 736 ± 9.71 | 175.52 ± 4.25 | 78.24 ± 2.35 | 18.9 ± 0.76 | 2260 ± 61 | 0.12 ± 0.01 |
3 | 681 ± 6.78 | 184.36 ± 5.73 | 83.63 ± 2.76 | 20.6 ± 1.32 | 2450 ± 72 | 0.14 ± 0.02 |
4 | 757 ± 10.12 | 144.65 ± 5.91 | 83.63 ± 2.95 | 17.0 ± 1.49 | 1930 ± 49 | 0.14 ± 0.02 |
5 | 743 ± 9.36 | 180.06 ± 4.74 | 89.08 ± 3.03 | 20.6 ± 0.93 | 2280 ± 67 | 0.12 ± 0.01 |
6 | 751 ± 6.92 | 163.36 ± 6.01 | 94.08 ± 3.12 | 16.6 ± 1.37 | 2180 ± 56 | 0.14 ± 0.02 |
7 | 737 ± 8.53 | 178.99 ± 5.38 | 75.58 ± 2.24 | 17.8 ± 1.52 | 2320 ± 42 | 0.15 ± 0.03 |
Statistic | Dowels Eco | Confirmat Eco | Screw Eco | Minifix MDF | Rafix MDF | Dowels MDF | Screw MDF | Confirmat MDF |
---|---|---|---|---|---|---|---|---|
No. of observations | 17 | 17 | 9 | 15 | 15 | 15 | 15 | 17 |
Mean (N·m) | 8.02 | 6.95 | 4.94 | 9.75 | 6.02 | 19.58 | 32.06 | 33.42 |
Minimum (N·m) | 5.45 | 4.31 | 4.12 | 8.13 | 5.00 | 17.19 | 24.06 | 27.19 |
Maximum (N·m) | 10.40 | 11.32 | 6.52 | 11.25 | 6.88 | 21.56 | 39.38 | 39.37 |
Median (N·m) | 8.01 | 6.49 | 4.56 | 9.38 | 6.25 | 19.69 | 30.94 | 33.75 |
Variance (N·m) | 2.07 | 4.47 | 0.61 | 1.11 | 0.44 | 1.53 | 19.97 | 11.99 |
St. Dev. (N·m) | 1.44 | 2.12 | 0.78 | 1.05 | 0.66 | 1.24 | 4.47 | 3.46 |
Covariance | 0.18 | 0.30 | 0.16 | 0.11 | 0.11 | 0.06 | 0.14 | 0.10 |
Type of Joint | Groups of Homogeneities (α = 0.05) | |||
---|---|---|---|---|
A | B | C | D | |
Confirmat MDF | 33.417 | |||
Screw MDF | 32.063 | |||
Dowels MDF | 19.583 | |||
Minifix MDF | 9.750 | |||
Dowels Eco | 8.016 | 8.016 | ||
Confirmat Eco | 6.951 | |||
Rafix MDF | 6.021 | |||
Screw Eco | 4.939 |
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Antov, P.; Jivkov, V.; Savov, V.; Simeonova, R.; Yavorov, N. Structural Application of Eco-Friendly Composites from Recycled Wood Fibres Bonded with Magnesium Lignosulfonate. Appl. Sci. 2020, 10, 7526. https://doi.org/10.3390/app10217526
Antov P, Jivkov V, Savov V, Simeonova R, Yavorov N. Structural Application of Eco-Friendly Composites from Recycled Wood Fibres Bonded with Magnesium Lignosulfonate. Applied Sciences. 2020; 10(21):7526. https://doi.org/10.3390/app10217526
Chicago/Turabian StyleAntov, Petar, Vassil Jivkov, Viktor Savov, Ralitsa Simeonova, and Nikolay Yavorov. 2020. "Structural Application of Eco-Friendly Composites from Recycled Wood Fibres Bonded with Magnesium Lignosulfonate" Applied Sciences 10, no. 21: 7526. https://doi.org/10.3390/app10217526
APA StyleAntov, P., Jivkov, V., Savov, V., Simeonova, R., & Yavorov, N. (2020). Structural Application of Eco-Friendly Composites from Recycled Wood Fibres Bonded with Magnesium Lignosulfonate. Applied Sciences, 10(21), 7526. https://doi.org/10.3390/app10217526