Know the Material
Thermoplastic Polyurethane
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Raw material
Solid pellets: Injection molders typically add up to 10% recycled materials. This practice can degrade the physical properties of the finished seals; but even when 100% virgin polymers are used, the Thermoplastic's physical properties are not stable as Universal Seal's Thermoset.
Molecular Structure
Thermoplastic is a linear polymer consisting of separate molecules and the application of excessive heat will cause the molecules to shift and the raw material to melt.
Thermoplastic Molecule
Thermoset Polyurethane
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Raw Material
Liquid resin and curing agent: Centrifugally cast Thermoset seals use only 100% virgin ram materials. Thermoset cast are free of internal voids (i.e. air bubbles) which can cause sudden failure and costly down-time.
Molecular Structure
Cross-links between Thermoset molecules form a heat stable matrix which maintains the physical properties of the seal as temperatures increase.
Thermoset Molecule
The centrifugal mold spins the liquid Thermoset Urethane at 3600 RPM first on a vertical axis then on a horizontal axis to create a strong finished seal providing durability, functionality and affordability
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Thermoplastic |
VS | Polyurethane |
|---|---|---|
|
Hardness, Shore A |
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|
90 |
92 | |
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Tensile
Modulus
|
||
|
1100 |
1400 | |
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Tensile
Modulus
|
||
|
2000 |
2600 | |
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Tensile Strength , PSI |
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|
5000 |
5800 | |
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Ultimate Elongation , % |
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|
450% |
420% | |
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Compression Set , Method 'B'% |
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|
35% |
24% | |
|
Bashore Rebound , % |
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|
40% |
45% | |
|
Universal Seal's Thermoset Unithane 292 A - outshines even premium Thermoplastic polyurethane in all of the above strength categories. The best molding method capable of taking advantage of these benefits is the Universal Seal centrifugal molding method. |
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Premium Thermoplastic |
Thermoset Polyurethane |
|
|---|---|---|
|
Hardness Shore A |
90 |
92 |
|
Tensile Modulus , PSI @ 100% Elongation |
1100 |
1400 |
|
Tensile Modulus , PSI @ 300% Elongation |
>2000
|
2600 |
|
Tensile Strength , PSI |
5000 |
5800 |
|
Ultimate Elongation , % |
450% |
420% |
|
Compression Set , Method 'B'% |
35% |
24% |
|
Bashore Rebound , % |
40% |
45% |
|
Universal Seal's Thermoset Unithane 292 A - outshines even premium Thermoplastic polyurethane in all of the above strength categories. The best molding method capable of taking advantage of these benefits is the Universal Seal centrifugal molding method. |
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