General Properties
Short Name:
Name:
TPS
Thermoplastic Styrene Elastomer
TPS is a tri-block copolymer with two styrene blocks (hard segments) on each end and an elastomeric block (soft segments, polydiene or hydrogenated polydiene) in the center. Characteristic properties of both hard and soft segments are also observed in the DSC curves.
Structural Formula
Properties
| Glass Transition Temperature | -80 to -50 (butadiene), 85 to 100 (styrene) °C |
|---|---|
| Melting Temperature | 150 to 160 (PP) °C |
| Melting Enthalpy | 20 J/g |
| Decomposition Temperature | 440 to 455°C |
| Young's Modulus | 10 to 200 MPa |
| Coefficient of Linear Thermal Expansion | - |
| Specific Heat Capacity | - |
| Thermal Conductivity | - |
| Density | 0.88 to 1.30 g/cm³ |
| Morphology | Thermoplastic elastomer, copolymer with hard and soft segments |
| General properties | Good hydrolysis resistance. High thermal resistance. Good aging resistance |
| Processing | Injection molding, extrusion, blow molding |
| Applications | Shoe industry (soles). Medical products. Screwdrivers, handles, electric tools (multi-component injection molding with hard and soft segments, whereas TPS represents the soft component) |
NETZSCH Measurement
| Instrument | DSC 204 F1 Phoenix® |
| Sample Mass | 15.25 mg |
| Isothermal Phase | 8 min |
| Heating/Colling Rates | 10 K/min |
| Crucible | Al, pierced lid |
| Atmosphere | N2 (40 ml/min) |
Evaluation
The present material is a blend from the tri-block copolymer and PP. In the 2nd heating (red), a glass transition can be seen at -68°C (midpoint), followed by a broad, endothermal effect (peak temperature -14°C), both of which are related to the butadiene component. A small glass transition for the polystyrene component can be seen at approx. 85°C (midpoint). This is followed by two endothermal effects with a total melting enthalpy of approx. 15 J/g; a smaller one at 115°C and a larger one at 154°C (peak temperature). The main peak is attributable to the melting of PP. The smaller peak at 115°C may be due to the presence of some PE. The DSC curves from the 1st and 2nd heatings are nearly identical.