Strong, Tailored, Biocompatible Shape‐Memory Polymer Networks

Shape‐memory polymers are a class of smart materials that have recently been used in intelligent biomedical devices and industrial applications for their ability to change shape under a predetermined stimulus. In this study, photopolymerized thermoset shape‐memory networks with tailored thermomechanics are evaluated to link polymer structure to recovery behavior. Methyl methacrylate (MMA) and poly(ethylene glycol) dimethacrylate (PEGDMA) are copolymerized to create networks with independently adjusted glass transition temperatures (Tg) and rubbery modulus values ranging from 56 to 92 °C and 9.3 to 23.0 MPa, respectively. Free‐strain recovery under isothermal and transient temperature conditions is highly influenced by the Tg of the networks, while the rubbery moduli of the networks has a negligible effect on this response. The magnitude of stress generation of fixed‐strain recovery correlates with network rubbery moduli, while fixed‐strain recovery under isothermal conditions shows a complex evolution for varying Tg. The results are intended to help aid in future shape‐memory device design and the MMA‐co‐PEGDMA network is presented as a possible high strength shape‐memory biomaterial.

[1]  C. Vallo.  Residual monomer content in bone cements based on poly(methyl methacrylate) , 2000 .

[2]  S. Miyazaki,et al.  Shape-memory materials and hybrid composites for smart systems: Part I Shape-memory materials , 1998 .

[3]  Melodie F Metzger,et al.  Photothermal properties of shape memory polymer micro‐actuators for treating stroke * , 2002, Lasers in surgery and medicine.

[4]  Yiping Liu,et al.  Thermomechanics of shape memory polymers: Uniaxial experiments and constitutive modeling , 2006 .

[5]  R. Langer,et al.  Biodegradable, Elastic Shape-Memory Polymers for Potential Biomedical Applications , 2002, Science.

[6]  C. Liang,et al.  Investigation of Shape Memory Polymers and Their Hybrid Composites , 1997 .

[7]  D. Mantovani,et al.  Shape Memory Materials for Biomedical Applications , 2002 .

[8]  Xiabin Jing,et al.  Polylactide-based polyurethane and its shape-memory behavior , 2006 .

[9]  Hisaaki Tobushi,et al.  Thermomechanical properties in a thin film of shape memory polymer of polyurethane series , 1996 .

[10]  D. Maitland,et al.  483 SHAPE MEMORY POLYMER NEUROVASCULAR STENTS. , 2006, Journal of Investigative Medicine.

[11]  Robert Langer,et al.  Convergence in biomedical technology , 2006, Nature Biotechnology.

[12]  Ward Small,et al.  Inductively Heated Shape Memory Polymer for the Magnetic Actuation of Medical Devices , 2005, IEEE Transactions on Biomedical Engineering.

[13]  R. Vaia,et al.  Remotely actuated polymer nanocomposites—stress-recovery of carbon-nanotube-filled thermoplastic elastomers , 2004, Nature materials.

[14]  Andreas Lendlein,et al.  Biodegradable, amorphous copolyester-urethane networks having shape-memory properties. , 2005, Angewandte Chemie.

[15]  A. Lendlein,et al.  Initiation of shape-memory effect by inductive heating of magnetic nanoparticles in thermoplastic polymers. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[16]  A Lendlein,et al.  Shape-memory polymers as stimuli-sensitive implant materials. , 2005, Clinical hemorheology and microcirculation.

[17]  Mao Xu,et al.  Polyurethanes having shape memory effects , 1996 .

[18]  Robin Shandas,et al.  Unconstrained recovery characterization of shape-memory polymer networks for cardiovascular applications. , 2007, Biomaterials.

[19]  M. Wagner,et al.  Development of a polymer stent with shape memory effect as a drug delivery system , 2003, Journal of materials science. Materials in medicine.

[20]  Patrick T. Mather,et al.  Review of progress in shape-memory polymers , 2007 .

[21]  J. Z. Hilt,et al.  Synthesis and temperature response analysis of magnetic-hydrogel nanocomposites. , 2007, Journal of biomedical materials research. Part A.

[22]  Duncan Maitland,et al.  Laser-activated shape memory polymer intravascular thrombectomy device. , 2005, Optics express.

[23]  M. Breese,et al.  Proton beam writing , 2007 .

[24]  Bianca Maria Baroli,et al.  Photopolymerization of biomaterials: issues and potentialities in drug delivery, tissue engineering, and cell encapsulation applications , 2006 .

[25]  Yiping Liu,et al.  Thermomechanical recovery couplings of shape memory polymers in flexure , 2003 .

[26]  E. Ushioda,et al.  Room-temperature-functional shape-memory polymers , 1995 .

[27]  S. Passy.  PMMA Implants: A New Way to Correct Body Defects without Surgery , 2003 .

[28]  R. Langer,et al.  Light-induced shape-memory polymers , 2005, Nature.

[29]  Marc Behl,et al.  Actively moving polymers. , 2006, Soft matter.

[30]  L. Yahia,et al.  Cold hibernated elastic memory foams for endovascular interventions. , 2003, Biomaterials.

[31]  D. Maitland,et al.  Shape‐memory behavior of thermally stimulated polyurethane for medical applications , 2007 .

[32]  Yiping Liu,et al.  Thermomechanics of the shape memory effect in polymers for biomedical applications. , 2005, Journal of biomedical materials research. Part A.

[33]  Dennis L. Matthews,et al.  Mechanical Properties of Mechanical Actuator for Treating Ischemic Stroke , 2002 .

[34]  Xuesi Chen,et al.  The influence of hard‐segments on two‐phase structure and shape memory properties of PCL‐based segmented polyurethanes , 2007 .