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US-20260125555-A1 - PCL/DCP BASED FREE STANDING THERMO-RESPONSIVE TWO WAY SHAPE MEMORY POLYMER GRIPPER

US20260125555A1US 20260125555 A1US20260125555 A1US 20260125555A1US-20260125555-A1

Abstract

Provided herein is a thermoresponsive two-way shape memory polymer comprising a crosslinking agent, a thermoplastic polyester, and a low-stiffness elastomer, wherein the crosslinking agent and the thermoplastic polyester are positioned internal to the elastomer. Also provided herein is a method of producing an actuator from a thermoresponsive two-way shape memory polymer comprising reacting a crosslinking agent with a thermoplastic polyester to produce a polymer and reacting the polymer with a low-stiffness elastomer to produce the two-way thermoresponsive shape memory polymer. The actuator is transitioned from a first position to a second position by application of a high temperature, and wherein the actuator is reversable from the second position back to the first position under application of a low temperature.

Inventors

  • Kamran A. Khan
  • Aamna Hameed

Assignees

  • Khalifa University of Science and Technology

Dates

Publication Date
20260507
Application Date
20241105

Claims (20)

  1. 1 . A thermoresponsive two-way shape memory polymer comprising: a crosslinking agent; a thermoplastic polyester; and a low-stiffness elastomer, wherein the crosslinking agent and the thermoplastic polyester are positioned internal to the elastomer.
  2. 2 . The thermoresponsive two-way shape memory polymer of claim 1 , wherein the crosslinking agent is dicumyl peroxide and wherein the thermoplastic polyester is polycaprolactone.
  3. 3 . The thermoresponsive two-way shape memory polymer of claim 1 , wherein the low-stiffness elastomer comprises natural rubbers, polyurethanes, polybutadienes, silicones, neoprene, or any combination thereof.
  4. 4 . The thermoresponsive two-way shape memory polymer of claim 1 , wherein the thermoresponsive two-way shape memory polymer comprises an actuation magnitude of greater than 7.0%.
  5. 5 . The thermoresponsive two-way shape memory polymer of claim 1 , wherein the thermoresponsive two-way shape memory polymer comprises a strain recovery of at least 49% when thermally cycled.
  6. 6 . The thermoresponsive two-way shape memory polymer of claim 1 , wherein the thermoresponsive two-way shape memory polymer is configured to be a freestanding two-way SMP gripping device.
  7. 7 . A gripping device comprising the thermoresponsive two-way shape memory polymer of claim 1 .
  8. 8 . A method of producing an actuator comprising a two-way thermoresponsive shape memory polymer comprising: reacting a crosslinking agent with a thermoplastic polyester to produce a polymer; reacting the polymer with a low-stiffness elastomer to produce the two-way thermoresponsive shape memory polymer, wherein the actuator is transitioned from a first position to a second position by application of a high temperature, and wherein the actuator is reversable from the second position back to the first position under application of a low temperature.
  9. 9 . The method of claim 8 , wherein the crosslinking agent is dicumyl peroxide.
  10. 10 . The method of claim 8 , wherein the thermoplastic polyester is polycaprolactone.
  11. 11 . The method of claim 8 , wherein the low-stiffness elastomer comprises natural rubbers, polyurethanes, polybutadienes, silicones, neoprene, or any combination thereof.
  12. 12 . The method of claim 8 , wherein the two-way thermoresponsive shape memory polymer comprises an actuation magnitude of greater than 7.0%.
  13. 13 . The method of claim 8 , wherein the two-way thermoresponsive shape memory polymer comprises a strain recovery of at least 49% when thermally cycled.
  14. 14 . A method of actuating a two-way thermoresponsive shape memory polymer comprising: programming the two-way thermoresponsive shape memory polymer; cooling the two-way thermoresponsive shape memory polymer; and re-shaping the two-way thermoresponsive shape memory polymer.
  15. 15 . The method of claim 14 , wherein programming the two-way thermoresponsive shape memory polymer comprises heating the two-way thermoresponsive shape memory polymer to a temperature greater than a melting temperature of the polymer.
  16. 16 . The method of claim 14 , wherein cooling the two-way thermoresponsive shape memory polymer comprises cooling the two-way thermoresponsive shape memory polymer to a temperature of 20° C. or less.
  17. 17 . The method of claim 14 , wherein the re-shaping further comprises: heating the two-way thermoresponsive shape memory polymer to a temperature of 60° C. or greater, wherein the heating causes the polymer to return to a semi-permanent position.
  18. 18 . The method of claim 14 , wherein the two-way thermoresponsive shape memory polymer comprises an actuation magnitude of greater than 7.0%.
  19. 19 . The method of claim 14 , wherein the two-way thermoresponsive shape memory polymer comprises a strain recovery of at least 49% when thermally cycled.
  20. 20 . The method of claim 14 , wherein programming the two-way thermoresponsive shape memory polymer causes the polymer to orient in a first position, wherein the first position is a linear position, and cooling the two-way thermoresponsive shape memory polymer causes the polymer to orient in a second position, wherein the second position is in a direction orthogonal to the first direction.

Description

BACKGROUND OF THE INVENTION Recently, smart materials such as shape memory polymers (SMPs) have attracted great attention for their ability to undergo controlled shape changes in response to external stimuli, typically temperature variations. This remote triggering capability enables precise actuation and deformation on demand, opening new possibilities for applications that require shape adaptability, such as biomedical devices, robotic systems, and deployable space structures. The unique combination of mechanical robustness, low weight, case of fabrication, and remote shape-changing capabilities positions SMPs as promising materials for the development of innovative solutions across various industries. A one-way SMP demonstrating one way shape memory effect (SME) is the simplest form, where the polymer is initially deformed at a temperature above its switching point (e.g., melting or glass transition temperature). This temporary shape is then fixed by cooling the material to room temperature. To recover its permanent shape, the SMP is reheated, completing one full shape memory cycle. However, a significant limitation of the one-way SME is that additional programming steps are required to initiate subsequent cycles, which can be impractical for certain applications. Thus, a two-way shape memory polymer that is capable of cycling from its initial state to a deformed state and subsequently back, without additional programming steps, is highly desirable. BRIEF SUMMARY OF THE INVENTION Covered embodiments of the present disclosure are defined by the claims, not this summary. This summary is a high-level overview of various aspects of the invention and introduces some of the concepts that are further described in the Detailed Description section below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification, any or all drawings and each claim. A shape memory polymer can include a crosslinking agent, a thermoplastic polyester, and a low-stiffness elastomer. The crosslinking agent and the thermoplastic polyester may be positioned internal to the elastomer. In some embodiments, the crosslinking agent may be dicumyl peroxide and the thermoplastic polyester may be polycaprolactone. In some embodiments, the low stiffness elastomer may include any one of natural rubbers, polyurethanes, polybutadienes, silicones, neoprene, or any combination thereof. In some embodiments, the thermoresponsive two-way shape memory polymer may include an actuation magnitude of greater than 7.0%. In some embodiments, the thermoresponsive two-way shape memory polymer can include a strain recovery of at least 49% when thermally cycled. In some embodiments, the thermoresponsive two-way shape memory polymer may be configured to be a freestanding two-way SMP gripper device. Described herein is a gripping device comprising the thermoresponsive two-way shape memory polymer. A method of producing an actuator can include reacting a crosslinking agent with a thermoplastic polyester to produce a polymer. The polymer may be reacted with a low-stiffness elastomer to produce the two-way thermoresponsive shape memory polymer. The actuator may be transitioned from a first position to a second position by application of a high temperature. In some embodiments, the actuator may be reversible from the second position back to the first position under application of a low temperature. In some embodiments, the crosslinking agent may be dicumyl peroxide. In some embodiments, the thermoplastic polyester may be a polycaprolactone. In yet other embodiments, the low-stiffness elastomer can include natural rubbers, polyurethanes, polybutadienes, silicones, neoprene, or any combination thereof. In some embodiments, the two-way thermoresponsive shape memory polymer may include an actuation magnitude of greater than 7.0%. In some embodiments, the two-way thermoresponsive shape memory polymer comprises a strain recovery of at least 49% when thermally cycled. A method of actuating a two-way thermoresponsive shape memory polymer can include first programming the two-way thermoresponsive shape memory polymer. The method may include cooling the two-way thermoresponsive shape memory polymer and subsequently re-shaping the two-way thermoresponsive shape memory polymer. In some embodiments, programming the two-way thermoresponsive shape memory polymer includes heating the two-way thermoresponsive shape memory polymer to a temperature greater than the melting temperature of the polymer. In some embodiments, cooling the two-way thermoresponsive shape memory polymer includes cooling the two-way thermoresponsive shape memory polymer to a temperature of 20° C. or less. In some embodiments, re-shaping may further include heating the two-way the