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Stress Relaxation Behaviour Modeling in Rigid Polyurethane (PU) Elastomeric Materials
Paweł Zielonka1, Krzysztof Junik2, Szymon Duda1
1Department of Mechanics, Materials Science and Biomedical Engineering, Faculty of Mechanical Engineering, Wroclaw University of Science and Technology, Smoluchowskiego 25, 50-370 Wrocław, Poland.
Materials (Basel, Switzerland)
|April 28, 2023
Summary
This study investigated the stress relaxation of rigid polyurethane (PUR) elastomers. A modified Kelvin-Voigt model accurately described the material
Area of Science:
- Materials Science
- Polymer Science
Background:
- Polyurethane (PU) is versatile due to tunable properties like mechanical strength and flexibility.
- Increasing demand for advanced materials drives interest in functional polyurethanes.
- Rigid polyurethane (PUR) elastomers offer unique characteristics for specialized applications.
Purpose of the Study:
- To analyze the rheological behavior of rigid polyurethane (PUR) elastomers.
- To investigate stress relaxation under varying strain conditions.
- To propose and validate a modified Kelvin-Voigt model for describing PUR stress relaxation.
Main Methods:
- Experimental examination of stress relaxation in PUR elastomers.
- Application of varying specified strains (50% to 100%).
- Utilizing a modified Kelvin-Voigt model for theoretical description.
Main Results:
- The rheological behavior of PUR elastomers was successfully characterized.
- Stress relaxation was observed and analyzed across different strain levels.
- The proposed modified Kelvin-Voigt model demonstrated effective validation for describing the observed phenomena.
Conclusions:
- The modified Kelvin-Voigt model provides an accurate description of stress relaxation in rigid polyurethane (PUR) elastomers.
- The findings support the use of this model for predicting PUR elastomer behavior under deformation.
- This research contributes to understanding and optimizing the performance of functional polyurethanes.
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