Star-PCL shape memory polymer (SMP) scaffolds with tunable transition temperatures for enhanced utility. Academic Article uri icon


  • Thermoresponsive shape memory polymers (SMPs) prepared from UV-curable poly(-caprolactone) (PCL) macromers have the potential to create self-fitting bone scaffolds, self-expanding vaginal stents, and other shape-shifting devices. To ensure tissue safety during deployment, the shape actuation temperature (i.e., the melt transition temperature or Tm of PCL) must be reduced from 55 C that is observed for scaffolds prepared from linear-PCL-DA (Mn 10 kg mol-1). Moreover, increasing the rate of biodegradation would be advantageous, facilitating bone tissue healing and potentially eliminating the need for stent retrieval. Herein, a series of six UV-curable PCL macromers were prepared with linear or 4-arm star architectures and with Mns of 10, 7.5, and 5 kg mol-1, and subsequently fabricated into six porous scaffold compositions (10k, 7.5k, 5k, 10k, 7.5k, and 5k) via solvent casting particulate leaching (SCPL). Scaffolds produced from star-PCL-tetraacrylate (star-PCL-TA) macromers produced pronounced reductions in Tm with decreased Mnversus those formed with the corresponding linear-PCL-diacrylate (linear-PCL-DA) macromers. Scaffolds were produced with the desired reduced Tm profiles: 37 C < Tm < 55 C (self-fitting bone scaffold), and Tm 37 C (self-expanding stent). As macromer Mn decreased, crosslink density increased while % crystallinity decreased, particularly for scaffolds prepared from star-PCL-TA macromers. While shape memory behavior was retained and radial expansion pressure increased, this imparted a reduction in modulus but with an increase in the rate of degradation.

published proceedings

  • J Mater Chem B

author list (cited authors)

  • Roberts, C. T., Beck, S. K., Prejean, C. M., Graul, L. M., Maitland, D. J., & Grunlan, M. A.

complete list of authors

  • Roberts, Courteney T||Beck, Sarah K||Prejean, C Mabel||Graul, Lance M||Maitland, Duncan J||Grunlan, Melissa A

publication date

  • March 2024