Table 2.
Processing parameters for birch (HW) and spruce (SW).
| Sample | Imp. temp. (°C) | Processing temp. (°C) | NaOH (M) | NaSH (M) | Vacuum (Yes/No) | Chip size (A/S/M/L) |
|---|---|---|---|---|---|---|
| SW(S/M/L) | 140 | 160 | 1 | 0.21 | No | S/M/L |
| HW(S/M/L) | 130 | 150 | 1 | 0.21 | Yes | S/M/L |
| HWA(V) | 130 | 150 | 1 | 0.21 | Yes/No | A |
| HWAL | 120 | 140 | 1 | 0.21 | No | A |
| HWAH | 140 | 160 | 1 | 0.21 | No | A |
| HWA0.75 | 130 | 150 | 0.75 | 0.16 | No | A |
| HWA0.5 | 130 | 150 | 0.5 | 0.11 | No | A |
Unsorted chips “A” is the average of all measured chips for each species. “S” refers to the smallest fraction of chips, “M” medium fraction, and “L” large fraction. High and low processing temperature is denoted by “H” and “L” respectively. The introduction of a vacuum impregnation is denoted by “V”. Chemical charge is denoted as the percentage of standard, “0.75” and “0.5” respectively.