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Updated: Jul 4, 2026
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Fabrication Process of Silicone-based Dielectric Elastomer Actuators
Published on: February 1, 2016
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Phase-Change Silicone Elastomers for Tough, Soft Actuators
Yoo Jin Lee1, Asaf Dana1,2, Sasha M George2
1Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, United States.
Macromolecules
|March 2, 2026
Summary
Researchers developed tough, shape-changing polydiethylsiloxane (PDES) elastomers for active biomedical devices. These mesomorphic materials exhibit significant reversible strain near body temperature, enabling novel soft actuator applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Biomedical Engineering
Background:
- Soft materials with controllable shape changes near ambient temperature are crucial for active devices interacting with biological systems.
- Conventional silicones often lack the required toughness and responsiveness for such applications.
Purpose of the Study:
- To synthesize and characterize responsive elastomers based on polydiethylsiloxane (PDES) for active device applications.
- To evaluate the mechanical properties, thermal responsiveness, and actuation capabilities of PDES elastomers.
Main Methods:
- Synthesis of mesomorphic PDES elastomers without reinforcing additives.
- Mechanical testing to determine toughness and tensile properties.
- Fabrication of twisting actuators and assessment of shape change cycles.
Main Results:
- PDES elastomers exhibit significantly enhanced toughness (8x PDMS, 4x Sylgard 184) due to their mesomorphic nature.
- Uniaxially stretched PDES elastomers generate 14% contractile strain upon heating from 0 to 40 °C.
- Strategies to minimize hysteresis in shape change cycles were identified.
Conclusions:
- Mesomorphic PDES elastomers offer a unique combination of toughness and temperature-triggered actuation near ambient conditions.
- These properties make PDES elastomers promising candidates for soft actuators in biomedical devices.
- Further development could optimize PDES for seamless integration with living organisms.
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