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Published on: January 19, 2016
Shape memory effect of thermoplastic segmented polyurethanes with self-complementary quadruple hydrogen bonding in
Yong Zhu1, Jinlian Hu, Yijun Liu
1Institute of Textiles and Clothing, Hong Kong Polytechnic University, Kowloon, Hong Kong, PRC.
The European Physical Journal. E, Soft Matter
|February 3, 2009
Summary
This study introduces a new thermoplastic shape memory polyurethane. This material exhibits excellent shape memory properties, with high recovery and fixity ratios, making it suitable for advanced applications.
Area of Science:
- Polymer Science
- Materials Science
- Materials Engineering
Background:
- Shape memory polymers (SMPs) are advanced materials capable of recovering their original shape when subjected to a stimulus.
- Thermoplastic polyurethanes (TPUs) are versatile polymers with tunable properties, but their shape memory performance can be limited.
- Incorporating specific functional groups can enhance the properties of TPUs, leading to improved shape memory effects.
Purpose of the Study:
- To synthesize and characterize a novel thermoplastic shape memory polyurethane.
- To investigate the impact of self-complementary quadruple hydrogen bonding on the shape memory behavior of TPUs.
- To evaluate the shape recovery and shape fixity performance of the developed material.
Main Methods:
- Synthesis of thermoplastic polyurethane incorporating self-complementary quadruple hydrogen bonding units in soft segments.
- Thermodynamic programming for shape memory effect induction.
- Differential Scanning Calorimetry (DSC) to determine glass transition temperature (Tg).
- Mechanical testing to assess shape recovery ratio (Rr) and shape fixity ratio (Rf).
Main Results:
- The introduction of quadruple hydrogen bonding significantly increased the glass transition temperature (Tg) from 28.3°C to 73.3°C.
- The material demonstrated a significant shape memory effect with high immediate shape recovery (95.8%) and shape fixity (95.9%).
- Even after 24 hours of relaxation, the material maintained substantial shape recovery (94%) and shape fixity (60%), outperforming the control sample.
Conclusions:
- Thermoplastic shape memory polyurethanes with self-complementary quadruple hydrogen bonding exhibit enhanced shape memory performance.
- The increased Tg due to hydrogen bonding allows for effective fixing of temporary deformation at room temperature.
- This material shows great potential for applications requiring reliable and robust shape memory behavior.
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