Calculation of rubber content
1. Concept of rubber content
The percentage of raw rubber in the rubber material;
The percentage of raw rubber in the rubber material to the total rubber material;
The mass of raw rubber in 100g (kg) of rubber material (g (kg))
2. Effect of rubber content
Rubber material properties (physical mechanical properties and processing properties)
Material cost
3. Calculation formula
Rubber content = raw rubber mass in rubber material/total rubber material mass x 100%
Calculation of rubber content
The calculation formula is:
Rubber content =100 / Total amount of formula x 100%
|
EPDM |
100 |
|
S |
1.5 |
|
TT |
1.5 |
|
M |
1.2 |
|
Zinc oxide |
5 |
|
SA |
1 |
|
N550 |
70 |
|
Antioxidant 4020 |
1.2 |
|
Protective wax |
1 |
|
Paraffin oil |
60 |
|
Total |
242.4 |
Rubber content = 100/242.4 x100% = 41.25%
Production formula:
|
Unified formula KG |
|
|
EPDM |
67 |
|
S |
1.005 |
|
TT |
1.005 |
|
M |
0.804 |
|
Zinc oxide |
3.35 |
|
SA |
0.67 |
|
N550 |
46.9 |
|
Antioxidant 4020 |
0.804 |
|
Protective wax |
0.67 |
|
Paraffin oil |
40.2 |
|
Total |
162.408 |
Rubber content = 67/162.408 x100% = 41.25%
Contains recycled rubber or rubber and plastic combined
Recycled rubber:
Calculate the rubber content in recycled rubber at 40-60% and use recycled rubber as filler, ignoring its rubber content
Rubber and plastic combined:
Resin as raw rubber (usually the basic formula of raw rubber + resin amount = 100)
Resin as filler (usually the basic formula of raw rubber amount = 100)
Contains compounding agent masterbatch, oil-filled and filler-filled rubber
Basic recipe:
Rubber content = 100 / Basic formula total amount x100%
|
Oil-filled EPDM |
150 |
|
S |
1.5 |
|
TT |
1.5 |
|
M |
1.2 |
|
Zinc oxide |
5 |
|
SA |
1 |
|
N550 |
70 |
|
Protective agent 4020 |
1.2 |
|
Protective wax |
1 |
|
Paraffin oil |
20 |
|
Total |
252.4 |
Rubber content = 100 /525.4 x100% =39.62%
Containing compounding agent masterbatch, oil-filled and filler rubber:
Production formula to calculate the rubber content:
Separate the pure rubber from the masterbatch, oil-filled and filler rubber in the formula and add it to the raw rubber.
|
Raw material name |
Dosage KG |
|
Oil-filled EPDM |
114 |
|
S |
1.14 |
|
TT |
1.14 |
|
M |
0.912 |
|
Zinc oxide |
3.8 |
|
SA |
0.76 |
|
N550 |
53.2 |
|
Protective agent 4020 |
0.912 |
|
Protective wax |
0.76 |
|
Paraffin oil |
15.2 |
|
N330 |
15.2 |
|
Total |
207.024 |
The raw rubber content in 114kg oil-filled rubber = 114 x 2/3 = 76kg
Rubber content = 76/207.024 x100% = 36.71%
Calculation of compound density
1. Concept
Rubber density is the mass of rubber per unit volume. The unit is kg/m3
2. Impact of rubber density
Product material cost
Product quality
3. Determination method
Measurement method: ordinary analytical balance, density balance, density bottle, etc.
Calculation method
4. Calculation formula
Theoretical density = total mass of rubber compound/total volume of rubber compound
5. Find the density from the basic recipe
Theoretical density = total mass of rubber material / total volume of rubber material
example:
|
Raw material name |
Basic recipe |
Density KG/M3 |
Volume |
|
natural rubber |
100 |
920 |
0.108696 |
|
Sulfur |
2.5 |
2050 |
0.001220 |
|
Accelerator M |
1 |
1420 |
0.000704 |
|
Zinc oxide |
4 |
5570 |
0.000718 |
|
Stearic acid |
2 |
920 |
0.002174 |
|
Carbon Black |
45 |
1800 |
0.025000 |
|
Pine tar |
4 |
830 |
0.004819 |
|
Total |
158.5 |
0.143331 |
Compound density KG/M3: 158.5/0.143331=1105.83
Calculated density is theoretical density, unvulcanized rubber density. Generally, theoretical density is less than vulcanized rubber density.
Because the volume of sulfur decreases after vulcanization, the cross-linking density increases.
6. Density from formula:
|
Raw material name |
Formula Quantity KG |
Density kg/m3 |
Volume M3 |
|
natural rubber |
33 |
920 |
0.03587 |
|
Sulfur |
0.99 |
2050 |
0.000483 |
|
Accelerator M |
0.495 |
1420 |
0.000349 |
|
Zinc oxide |
1.32 |
5570 |
0.000237 |
|
Stearic acid |
0.33 |
920 |
0.000359 |
|
Carbon Black |
21.45 |
1800 |
0.011917 |
|
Pine tar |
1.32 |
830 |
0.00159 |
|
Total |
58.905 |
0.050804 |
Compound density KG/M3:
58.905 / 0.050804= 1159.46
