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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
|