Temperature-Memory Effect of Copolyesterurethanes and their Application Potential in Minimally Invasive Medical Technologies

• Published in: Advanced functional materials Vol. 22; no. 14; pp. 3057 - 3065
• Main Authors: Kratz, Karl, Voigt, Ulrike, Lendlein, Andreas
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 24-07-2012; WILEY‐VCH Verlag
• Subjects: biomaterials; shape-memory polymers; stimuli-sensitive materials; temperature-memory effects
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201200211

Minimally invasive surgery often requires devices that can change their geometry or shape when placed inside the body. Here, the potential of thermoplastic temperature‐memory polymers (TMP) for the design of intelligent devices, which can be programmed by the clinician to individually adapt their shifting geometry and their response temperature Tsw to the patient's needs, is explored. Poly(ω‐pentadecalactone) as hard segments and poly(ϵ‐caprolactone) segments acting as crystallizable controlling units for the temperature‐memory effect (TME) are chosen to form multiblock copolymers PDLCL. These components are selected according to their thermal properties and their good biocompatibility. Response temperatures obtained under stress‐free and constant strain recovery can be systematically adjusted by variation of the deformation temperature in a temperature range from 32 °C to 65 °C, which is the relevant temperature range for medical applications. The working principle of TMP based instruments for minimally invasive surgical procedures is successfully demonstrated using three temperature‐memory catheter concepts: individually programmable TM‐catheter, an in‐situ programmable TM‐catheter, and an intelligent drainage catheter for gastroenterology.
Biomedical applications often require intelligent devices that can perform self‐sufficient shape changes or can be fixed in an adapted geometry. The working principle of temperature‐memory catheters based on copolyesterurethanes containing poly(ω‐pentadecalactone) and poly(ϵ‐caprolactone) segments as controlling units for the temperature‐memory effect are explored. The response temperatures of such polymers can be adjusted in a range relevant for biomedical applications.