1 Introduction
2 Materials and methods
2.1 Treatment of the wood specimens
Chemical characterisation | Trade name | Concentration |
---|---|---|
Sodium water glass with additives | BETOL 39 T3 (Woellner, Ludwigshafen, Germany) | 15 wt/wt |
N-methylol compound, 1,3-dimethylol-4,5-dihydroxyethylene urea | DMDHEU (BASF, Ludwigshafen, Germany) | 1.3 M |
2.2 Determination of pH-values
2.3 Blue stain test
Rating (mean value) | Description |
---|---|
0 | Not blue stained |
1 | Insignificantly blue stained, the surface exhibits only |
Individual small blue stained spots with the largest | |
Diameter of 2 mm and a maximum of 5% of the sample surface | |
2 | A maximum of 20% of the surface is blue stained |
3 | Over 20% to 50% of the surface is blue stained |
4 | Over 50% to 75% of the surface is blue stained |
5 | Strongly blue stained, more than 75% of the surface |
2.4 Sugar analysis by high pressure liquid chromatography (HPLC)
3 Results and discussion
Treatments | pH-values | |
---|---|---|
Scots pine | Beech | |
Untreated | 5.5 (±0.2) | 5.9 (±0.2) |
DMDHEU | 3.8 (±0.1) | 4.2 (±0.1) |
Water glass before CO2 storage | 12.0 (±0.1) | 11.2 (±0.3) |
Water glass after CO2 storage | 10.1 (±0.7) | 9.7 (±0.6) |
Treatments | Mean value and standard deviation of blue stain on the surface in contact with vermiculite [%] | Mean value and standard deviation of blue stain on the reverse surface [%] | ||
---|---|---|---|---|
Scots pine | Beech | Scots pine | Beech | |
Untreated | 89 (±5) | 77 (±9) | 60 (±4) | 57 (±8) |
DMDHEU | 49 (±6) | 43 (±4) | 4 (±1) | 8 (±3) |
Water glass | 2 (±2) | 15 (±4) | 1 (±1) | 3 (±1) |
Treatments | Classification of the surface in contact with vermiculite | Classification of the reverse surface | ||
---|---|---|---|---|
Scots pine | Beech | Scots pine | Beech | |
Untreated | 5 | 5 | 4 | 4 |
DMDHEU | 3 | 3 | 1 | 2 |
Water glass | 1 | 2 | 1 | 1 |
Untreated [mg/g dry wood] | DMDHEU [mg/g dry wood] | Water glass [mg/g dry wood] | ||||
---|---|---|---|---|---|---|
Before test | After test | Before test | After test | Before test | After test | |
Arabinose | nq | nq | 2.28 (±0.02) | 1.78 (±0,77)*
| nq | nq |
Fructose | nq | 0.23 (±0.13) | nq | nq | nq | nq |
Galactose | 1.09 (±0.03) | 1.34 (±0.23)*
| 12.90 (±0.42) | 8.99 (±0,34)*
| nq | nq |
Glucose | nq | nq | 11.09 (±3.62) | 1.95 (±0,96)*
| nq | nq |
Xylose | 0.04 (±0.02) | nq | 9.92 (±0.17) | nq*
| nq | nq |
Mannose | 4.29 (±0.04) | nq*
| nq | nq | 3.73 (±0.03) | 3.98* (±0.19) |
Total amount | 5.42 (±0.09) | 1.57 (±0.36) | 36.19 (±4.23) | 12.72 (±2.27) | 3.73 (±0.03) | 3.98 (±0.19) |
Untreated [mg/g dry wood] | DMDHEU [mg/g dry wood] | Water glass [mg/g dry wood] | ||||
---|---|---|---|---|---|---|
Before test | After test | Before test | After test | Before test | After test | |
Fructose | 3.87 (±1.11) | nq*
| nq | nq | nq | nq |
Galactose | 1.02 (±0.01) | 1.64 (±0.05)*
| 9.80 (±1.07) | 13.13 (±0,93)*
| 1.56 (±0.05) | 2.14* (±0.20) |
Glucose | 4.33 (±1.59) | nq*
| nq | nq | nq | nq |
Mannose | 3.97 (±0.03) | nq*
| nq | nq | 3.89 (±0.03) | 4.19* (±0.06) |
Total amount | 13.19 (±2.74) | 1.64 (±0.05) | 9.80 (±1.07) | 13.13 (±0.93) | 5.45 (±0.08) | 6.33 (±0.26) |