Table 4 Changes in colour, tensile breaking load (N), and extension (%) of substitute textiles during accelerated ageing (80°C, 58% RH)
Sample | Extent of ageing (weeks) | Difference in colour (aged versus unaged) | Mean tensile properties | ||||
|---|---|---|---|---|---|---|---|
|  |  | ΔE00* | ΔL* | Δa* | Δb* | Breaking load (N) | Extension (%) |
WU | 0 | 0.00 | 0.00 | 0.00 | 0.00 | NDa | ND |
|  | 1 | 1.14 | 0.05 | −0.40 | 1.38 | ND | ND |
|  | 2 | 1.33 | 0.32 | −0.48 | 1.58 | ND | ND |
|  | 3 | 1.75 | 0.17 | −0.61 | 2.16 | ND | ND |
|  | 4 | 2.44 | −0.22 | −0.72 | 3.17 | ND | ND |
SU | 0 | 0.00 | 0.00 | 0.00 | 0.00 | 70.2 (4.9)b | 28.2 (1.7)b |
|  | 1 | 1.04 | −0.06 | −0.32 | 1.00 | 64.2 (4.4) | 25.2 (0.8) |
|  | 2 | 1.57 | 0.00 | −0.44 | 1.54 | 65.5 (4.8) | 24.9 (2.5) |
|  | 3 | 2.16 | −0.48 | −0.54 | 2.17 | 62.3 (4.7) | 24.8 (2.7) |
|  | 4 | 2.59 | −0.40 | −0.57 | 2.70 | 61.6 (4.3) | 21.7 (2.1) |
AU | 0 | 0.00 | 0.00 | 0.00 | 0.00 | 239.9 (43.1) | 3.9 (0.5) |
|  | 1 | 2.39 | −2.17 | 0.67 | 2.78 | 255.5 (38.1) | 3.7 (0.5) |
|  | 2 | 3.08 | −2.82 | 1.05 | 3.43 | 262.8 (47.3) | 3.8 (0.5) |
|  | 3 | 3.03 | −1.63 | 1.39 | 4.22 | 250.0 (40.3) | 3.9 (0.6) |
|  | 4 | 3.95 | −2.64 | 1.76 | 5.29 | 248.8 (28.9) | 3.5 (0.5) |
CU | 0 | 0.00 | 0.00 | 0.00 | 0.00 | 117.1 (9.2) | 9.1 (0.8) |
|  | 1 | 0.62 | −0.15 | −0.10 | 0.61 | 101.9 (15.7) | 8.2 (1.0) |
|  | 2 | 1.20 | 0.06 | −0.06 | 1.26 | 107.2 (11.6) | 8.2 (0.7) |
|  | 3 | 1.52 | −0.84 | −0.07 | 1.48 | 107.1 (8.3) | 8.6 (0.5) |
|  | 4 | 1.82 | −0.28 | −0.06 | 1.92 | 108.2 (11.0) | 8.1 (0.5) |
Wp1 | 0 | 0.00 | 0.00 | 0.00 | 0.00 | ND | ND |
| Â | 1 | ND | ND | ND | ND | ND | ND |
|  | 2 | 2.74 | −0.50 | −0.39 | 2.73 | ND | ND |
|  | 3 | 3.64 | 0.42 | −0.46 | 3.70 | ND | ND |
|  | 4 | 5.70 | 3.33 | −0.62 | 5.21 | ND | ND |
Sp1 | 0 | 0.00 | 0.00 | 0.00 | 0.00 | 62.9 (4.9) | 25.0 (2.6) |
|  | 1 | 1.07 | −0.61 | −0.17 | 1.13 | 55.6 (6.1) | 19.7 (1.4) |
|  | 2 | 1.78 | −0.31 | −0.30 | 1.98 | 46.0 (3.7) | 14.5 (0.7) |
|  | 3 | 2.15 | 0.25 | −0.41 | 2.37 | 34.2 (9.4) | 13.2 (1.5) |
|  | 4 | 3.27 | 2.02 | −0.39 | 3.24 | 33.2 (6.1) | 10.1 (1.8) |
Ac1 | 0 | 0.00 | 0.00 | 0.00 | 0.00 | 105.9 (18.3) | 2.1 (0.3) |
| Â | 1 | 3.04 | 0.24 | 0.11 | 3.17 | 14.6 (4.9) | 1.8 (0.4) |
|  | 2 | 4.54 | −0.37 | 0.63 | 4.64 | 6.5 (1.9) | 1.0 (0.3) |
|  | 3 | 5.33 | −0.68 | 1.20 | 5.34 | NDc | NDc |
|  | 4 | 4.96 | −2.00 | 1.08 | 4.75 | NDc | NDc |
Cc1 | 0 | 0.00 | 0.00 | 0.00 | 0.00 | 68.3 (5.3) | 6.9 (0.7) |
|  | 1 | 7.35 | −4.23 | 0.30 | 6.92 | 29.5 (3.9) | 4.9 (0.6) |
|  | 2 | 10.49 | −4.68 | 1.29 | 10.55 | 13.0 (0.4) | 3.7 (0.6) |
|  | 3 | 12.15 | −5.71 | 2.29 | 12.24 | 7.7 (1.1) | 3.5 (0.2) |
|  | 4 | 13.24 | −6.72 | 3.02 | 13.22 | 6.2 (0.7) | 3.5 (0.2) |