Shape Memory Polymers

Shape memory polymers (SMPs) are “intelligent” polymer based materials with impressive shape recovery abilities. These materials change their form as a response to an external or internal stimulus such as mechanical stress, temperature, pH, electric and magnetic fields. Amongst all these effects, temperature and mechanical stress are practically the most important.  SMPs obtain the desired form through temperature change and mechanical force and revert to their original shape upon the removal of force and increase of temperature. This behavior is called the shape memory effect. Important parameters of shape memory effect for polymers are;

• Glass transition temperature (T_g)
• Crystallization/melting transition temperature (T_m)
• Tensile strength
• Elongation
• Hardness

Shape memory polymers are utilized in various different applications due to their intriguing shape recovery ability, chemical stability, biodegradability, and low density. Major application areas of SMPs are listed as;

• Biomedical applications (stents, sutures, microdevices…)
• Adjustable Braille paper
• Soft Robots
• Smart textiles