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Properties of Unfilled and Filled PTFE |
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Property |
Unit |
Test Method (ASTM) |
100% Pure PTFE |
25% Carbon Filled PTFE |
25% Glass Filled PTFE |
15% Graphite Filled PTFE |
40% Bronze Filled PTFE |
60% Bronze Filled PTFE |
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Specific Gravity |
- |
D 1457 |
2.14 - 2.18 |
2.08 - 2.1 |
2.22 - 2.25 |
2.13 - 2.18 |
3.1 - 3.22 |
3.85 - 3.95 |
Bulk Density |
g/1 |
D 1457 |
700 + 100 |
500 + 40 |
475+ 50 |
500+ 40 |
900 + 50 |
1050 + 50 |
Tensile Strength |
kg/cm2 |
D 1457 |
250 - 310 |
160 - 175 |
130 - 150 |
140 - 210 |
180 - 240 |
125 - 150 |
Elongation at Break |
% |
D 1457 |
280 - 300 |
80 - 110 |
210 - 270 |
100 - 180 |
240 - 320 |
150 - 200 |
Hardness |
Shore D |
D 2240 |
50 - 65 |
71 - 73 |
66 - 68 |
62 - 65 |
67 - 69 |
71 - 73 |
Coeff. of Friction |
-- |
LNP Std. |
0.06 |
0.13 |
0.12 |
0.07 |
0.12 |
0.13 |
Deformation after 24 Hours at 230C 140 kg/cm2C |
% |
D-621 |
15 |
5 |
11 |
9 |
5 |
5 |
Deformation after 24 Hours at 2600C 40 kg/cm2 |
% |
D-621 |
31 |
11 |
21 |
16 |
14 |
12.5 |
Flexural Strength |
kgf/cm2 |
D-790 |
57 |
96 |
42 |
63 |
- |
80 |
Impact Strength |
Cmkg/cm2 |
D-256 |
- |
- |
- |
- |
- |
- |
A - 200C |
- |
- |
9 |
7.5 |
9.5 |
- |
- |
11 |
B - 200C |
- |
15 |
10 |
11 |
- |
- |
10 |
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Dielectric Strangth |
KV/mm |
D-149 |
24 |
2 |
12 |
- |
Conductive |
Conductive |
Volume Resistivity |
Ohm-cm |
D-257 |
1010 |
104 |
1015 |
1014 |
- |
1017 |
Surface Resistivity |
Ohm |
D-257 |
1017 |
107 |
1015 |
1014 |
- |
109 |
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Heat Resistance |
0C |
- |
-250 to 260 |
-250 to 260 |
-250 to 260 |
-250 to 260 |
-250 to 260 |
- |
Thermal Conductivity |
10-4Cal.
Cm.Sec. Deg. |
Cento Fitch |
6 |
13 |
9 |
11 |
- |
19 |
Linear Expansion |
% |
D-696 |
Axial Redial |
Axial Redial |
Axial Redial |
Axial Redial |
Axial Redial |
Axial Redial |
A 30 to 1500C |
- |
- |
1.5 1.5 |
1.2 1.0 |
1.2 1.5 |
- |
- |
1.1 0.9 |
B 30 to 2000C |
- |
- |
2.4 2.4 |
1.9 1.5 |
2.2 1.0 |
- |
- |
1.8 1.5 |
C 30 to 2500C |
- |
- |
3.4 3.6 |
2.7 2.4 |
3.2 1.4 |
2.15 1.6 |
- |
2.5 2.2 |
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Chemical Resistance |
PTFE is almost completely chemically inert material. Molten or dissolved alkali metals degrade PTFE by abstracting fluorine from the molecule. Apart from these PTFE resin is not at all attacked by any of the acids, bases and slovents.
Filled PTFE has inferior chemical resistance because of the presence of the particular filler. |
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