Unconstrained recovery characterization of shape-memory polymer networks for cardiovascular applications.
Shape-memory materials have been proposed in biomedical device design due to their ability to facilitate minimally invasive surgery and recover to a predetermined shape in vivo. Use of the shape-memory effect in polymers is proposed for cardiovascular stent interventions to reduce the catheter size for delivery and offer highly controlled and tailored deployment at body temperature. Shape-memory polymer networks were synthesized via photopolymerization of tert-butyl acrylate and poly(ethylene glycol) dimethacrylate to provide precise control over the thermomechanical response of the system. The free recovery response of the polymer stents at body temperature was studied as a function of glass transition temperature (T(g)), crosslink density, geometrical perforation, and deformation temperature, all of which can be independently controlled. Room temperature storage of the stents was shown to be highly dependent on T(g) and crosslink density. The pressurized response of the stents is also demonstrated to depend on crosslink density. This polymer system exhibits a wide range of shape-memory and thermomechanical responses to adapt and meet specific needs of minimally invasive cardiovascular devices.
Yakacki
Christopher Michael
CM
Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO 80309-0427, USA.
Shandas
Robin
R
Lanning
Craig
C
Rech
Bryan
B
Eckstein
Alex
A
Gall
Ken
K
D000179:Acrylates / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D001807:Blood Vessel Prosthesis; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry*; D011474:Prosthesis Design; D015607:Stents; D013696:Temperature
D000179:Acrylates; D001672:Biocompatible Materials; D011108:Polymers