Thermal Responsive Shape Memory Polymers for Biomedical Applications

Most polymers used in clinical applications today are materials that have been developed originally for application areas other than biomedicine. On the other side, different biomedical applications are demanding different combinations of material properties and functionalities. Compared to the intrinsic material properties, a functionality is not given by nature but result from the combination of the polymer architecture and a suitable process. Examples for functionalities that play a prominent role in the development of multifunctional polymers for medical applications are biofunctionality (e.g. cell or tissue specificity), degradability, or shape-memory functionality. In this sense, an important aim for developing multifunctional polymers is tailoring of biomaterials for specific biomedical applications. Here the traditional approach, which is designing a single new homo- or copolymer, reaches its limits. The strategy, that is applied here, is the development of polymer systems whose macroscopic properties can be tailored over a wide range by variation of molecular parameters. The Shape-memory capability of a material is its ability to trigger a predefined shape change by exposure to an external stimulus. A change in shape initiated by heat is called thermally-induced shape-memory effect. Thermally, light-, and magnetically induced shape-memory polymers will be presented, that were developed especially for minimally invasive surgery and other biomedical applications. Furthermore triple-shape polymers will be introduced, that have the capability to perform two subsequent shape changes. Thus enabling more complex movements of a polymeric material.

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Biomedical applications of shape-memory polymers: how practically useful are they?

Science China Chemistry ◽

10.1007/s11426-013-5061-z ◽

2014 ◽

Vol 57 (4) ◽

pp. 476-489 ◽

Cited By ~ 29

Author(s):

YeeShan Wong ◽

JenFong Kong ◽

Leonardus K. Widjaja ◽

Subbu S. Venkatraman

Keyword(s):

Shape Memory ◽

Biomedical Applications ◽

Shape Memory Polymers

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A mini review: Shape memory polymers for biomedical applications

Frontiers of Chemical Science and Engineering ◽

10.1007/s11705-017-1632-4 ◽

2017 ◽

Vol 11 (2) ◽

pp. 143-153 ◽

Cited By ~ 47

Author(s):

Kaojin Wang ◽

Satu Strandman ◽

X. X. Zhu

Keyword(s):

Shape Memory ◽

Biomedical Applications ◽

Shape Memory Polymers

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Micromechanical Modelling of Shape Memory Polymers

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.54.137 ◽

2008 ◽

Vol 54 ◽

pp. 137-142 ◽

Cited By ~ 5

Author(s):

Markus Böl ◽

Stefanie Reese

Keyword(s):

Shape Memory ◽

Biomedical Applications ◽

Three Dimensional ◽

Coupled Model ◽

Shape Memory Polymers ◽

Material Behaviour ◽

Thermomechanical Loading ◽

Temperature Changes ◽

Mechanical Interpretation ◽

Biomedical Field

Shape memory materials represent a promising class of dual-shape materials that can move from one shape to another in response to a stimulus such as light, heat, electricity or magnetism. In this regard, the biomedical field is showing large interest in this class of materials, especially in shape memory polymers (SMPs), whose mechanical properties make them extremely attractive for many biomedical applications. However, diverse characteristics including also the mechanical behaviour are still part of research. In this contribution the shape memory properties of polymers will be quantified by cyclic thermomechanical investigations. One cycle includes the "programming" of the sample and the recovery of its permanent shape. To describe this phenomenon, a three-dimensional thermomechanical coupled model is proposed. This macromechanical constitutive model is based on the physical understanding of the material behaviour and a mechanical interpretation of the stress-strain-temperature changes observed during thermomechanical loading. The main focus of this work is the influence of both, the material constants and heat transfer boundary conditions on the response of shape memory polymers. Therefore we illustrate different general simulations as well as examples of application.

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