The high level of variation that can be achieved in polyurethane chemistry makes it possible to produce Desmopan® with a very wide range of Young’s moduli.
The range up to 1000 MPa is covered by non-reinforced grades. Reinforced Thermoplastic Polyurethanes grades (brand name: Desmovit) can attain considerably higher moduli.
The graphic shows the Young’s modulus range for Thermoplastic Polyurethanes and RTPU compared to the range for other materials.
Young’s modulus (modulus of elasticity) is established from the tensile test to DIN 53504 on an S1 specimen to DIN EN ISO 3167, employing a testing rate of 2 mm/min. Young’s modulus is calculated as the ratio of stress to strain from the initial gradient of the stress-strain curve.
In the case of plastics, Young’s modulus has been seen to be dependent on the following parameters:
- Orientation of the macromolecules and fillers
- Moisture content
- Stressing rate and duration
- Specimen geometry
- Test setup
Stiffness as a function of temperature
The dependence on temperature is shown in the following diagrams on the basis of different raw materials and hardnesses.