Cobb's test results
| Composite Cobb1800 | Mass of dry composite (before) /g | Mass of wet composite (after) /g | Mass of water absorbed /g | Notes/ observation | Water absorbed per unit area (g/m^2) | |
|---|---|---|---|---|---|---|
| Pure alginate | 1 | 7.77 | 9.07 | 1.3 | 139.5718366 | |
| 2 | 7.77 | 8.76 | 0.99 | 106.2893217 | ||
| 3.0 % w/v chitosan | 1 | 8.89 | 9.85 | 0.96 | 103.0684331 | |
| 2.5 % w/v chitosan | 1 | 9.43 | 11.7 | 2.27 | A lot of leak | 243.7138992 |
| 2.0 % w/v chitosan | 1 | 8.71 | 10.92 | 2.21 | 237.2721221 | |
| 1.0 % w/v chitosan | 1 | 8.61 | 9.56 | 0.95 | 101.9948036 |
| Composite Cobb60 | Mass of dry composite (before) /g | Mass of wet composite (after) /g | Mass of water absorbed /g | Notes/ observation | Water absorbed per unit area (g/m^2) | |
| Pure alginate | 1 | 8.13 | 8.27 | 0.14 | 15.03081317 | |
| 2 | 7.77 | 7.95 | 0.18 | 19.32533121 | ||
| 2.5% w/v chitosan | 1 | 7.99 | 8.52 | 0.53 | 56.90236413 | |
| 2 | 9.18 | 9.58 | 0.4 | 42.94518048 | ||
| 3% w/v chitosan | 1 | 9.23 | 9.59 | 0.36 | 38.65066243 | |
| 2% w/v chitosan | 1 | 8.87 | 9.69 | 0.82 | 88.03761998 | |
| 1% w/v chitosan | 1 | 8.92 | 9.1 | 0.18 | 19.32533121 |
Extension: Results of Cobb's Test before and after refrigeration
| Sodium Alginate (g/m^2) | Sorbic Acid (g/m^2) | |||
|---|---|---|---|---|
| Cobb60 | Cobb1800 | Cobb60 | Cobb1800 | |
| Room Temperature | 17.2 | 123.5 | 29 | 191.1* |
| Refrigerated | 36.5 | 108.4 | 29 | 104.1 |
Paste formation
| No. | Mass of sodium alginate /g | Mass of chitosan /g | %w/v sodium alginate /% | %w/v chitosan /% | Time taken to become homogenous /min | Notes/observation |
|---|---|---|---|---|---|---|
| 1 | 1.007 | 0 | 2 | 0 | 24 | Was not completely homogenous. |
| 2 | 1.0011 | 0 | 2 | 0 | 65 | Translucent fluid. |
| 3 | 1.0011 | 1.2493 | 2 | ~2.5 | 30 | Cloudy, homogenous fluid. |
| 4 | 1.007 | 1.5011 | 2 | ~3.0 | 45 | |
| 5 | 1.0004 | 0.5008 | 2 | 1 | 35 | |
| 6 | 1.0032 | 1.0005 | 2 | 2 | 30 |
Titration results
| Mass CaCl2/ g | Mass eriochrome black T indicator / g | Initial mass of paper / g | Mass of sodium alginate on paper / g | Mass of paper + calcium alginate after dipping in 5% w/v CaCl2solution / g * | Initial burette reading / cm3 | Final burette reading / cm3 | Titre value / cm3 | |
|---|---|---|---|---|---|---|---|---|
| 5% w/v CaCl2solution Test 1 | 1.2504 | 1.0002 | N/A | N/A | N/A | 10.7 | 32.15 | 21.45 |
| 5% w/v CaCl2solution Test 2 | 1.2506 | 0.9992 | N/A | N/A | N/A | 8.1 | 29.1 | 21 |
| Calcium alginate Test 1 | 1.2501 | 1 | 1.9465 | 0.7635 | 3.93 | 0.7 | 19.7 | 19 |
| Calcium alginate Test 2 | 1.2496 | 1.0004 | 2.138 | 0.812 | 3.3 | 19.7 | 40.4 | 20.70 (air bubble) |
| Calcium alginate Test 3 | 1.2483 | 1.0011 | 2.1993 | 0.9507 | 3.7 | 16 | 35.35 | 19.35 |
| Hydrolysed Test 1 | 1.2503 | 1.0001 | 2.232 | 2.458 | 5.03 | 4.3 | 24.6 | 20.3 |
| Hydrolysed Test 2 | 1.2475 | 1.0004 | 2.221 | 2.109 | 4.49 | 20.7 | 40 | 19.3 |
| Hydrolysed Test 3 | 1.252 | 0.9995 | 2.36 | 2.11 | 4.74 | 7.1 | 27 | 19.9 |
Strength test
| Sodium alginate | Sodium alginate + sorbic acid | |
|---|---|---|
| Mass of sand required to break membrane / g | 163.11 | 165.02 |
Extension:
| Sodium Alginate | Initial Area / x 10-3m2 | Area after spraying CaCl2/ x 10-3m2 | Area after refrigeration / x 10-3m2 |
|---|---|---|---|
| Room Temperature | 9.5 | 7.7 | 5.3 |
| Refrigerated | 9.5 | 5.7 | 4.9 |
| 0.3 % Sorbic Acid | Initial Area / x 10-3m2 | Area after spraying CaCl2/ x 10-3m2 | Area after refrigeration / x 10-3m2 |
|---|---|---|---|
| Room Temperature | 9.5 | 7.2 | 5.9 |
| Refrigerated | 9.5 | 7.4 | 6.4 |