Shape memory polymer degradable

Degradable implants, shape-memory polymers in, 22 355 Degradable-pendant-chain hydrogels, 13 741... 

Wang, L. S., Chen, H. C., Xiong, Z. C., Pang, X. B., and Xiong, C. D. 2010. Novel degradable compound shape-memory polymer blend Mechanical and shape-memory properties. Materials Letters 64 284-286. 

Guo, W., Kang, H., Chen, Y., Guo, B., and Zhang, L. (2012) Stronger and faster degradable biobased poly(propylene sebacate) as shape memory polymer by incorporating boehmite nanoplatelets. ACS Appl Mater. Interfaces, 4 (8), 4006-4014. 

Madbouly, S.A. and Lendlein, A. (2012) Degradable polyurethane/soy protein shape-memory polymer blends prepared via environmentally-friendly aqueous dispersions. Macromol. Mater. Eng., 297 (12), 1213-1224. 

In the fourth chapter, biomedical applications of shape-memory polymers are presented. Vascular, orthopaedic, and neuronal applications are elaborated to illustrate how SMP can improve the standard of treatment. Additionally, the practical challenges of the development of SMP for biomedical devices are described. The fifth chapter deals with multifunctional SMP. The combination of the shape-memory effect with hydrolytic degradability and the capability to release a drug in a controlled way are described as an example of multifunctionality. Drug loading and release, as well as the effects of the drugs on the shape-memory properties are discussed and potential applications in minimally-invasive surgery are outlined. 

Wischke, C., Neffe, A. T., Steuer, S., Lendlein, A. (2009). Evaluation of a degradable shape-memory polymer network as matrix for controlled drug release. Journal of Controlled Release, 138(3), 243—250. 

For biomedical applications, a thermal transition of the segment chains in the range between room and body temperature is of great interest. Suitable segments for degradable shape memory polymers can be found by regarding... 

Hydrolytic degradation of shape memory polymers at 70 °C in buffered solution of pH 7 loss in relative sample mass ( PDC27 PDC31 PDC40 A PDL30). 

Biodegradable shape memory polymers are candidates for the next promising generation of implant materials. The fact that these materials belong to a polymer system allows the adjustment of certain properties in a wide range, e.g. mechanical properties and degradation behaviour. Today, such materials can be synthesized in a kilogram scale. 

Choi, N.Y and A. Lendlein (2007), Degradable shape-memory polymer networks from ohgo (L-lactide)-ran-glycolide dimethacrylates. Soft Matter, 3(7) pp. 901-909. 

Goo et al. investigated the actuation durability of a conducting shape memory polyurethane/MWNT (CSMPU) actuator and concluded that the number of cycles at breaking decreased, as the actuation temperature increased (108). The possible reason is that more material degradation of CSMPU can be induced due to rapid and large movement of polymer chains as the actuation temperature increases. For a CSMPU actuator, the authors confirmed that an actuation temperature that is higher than the transition temperature produces a rapid response but low durability. 

Yang, J., Liu, E, Yang, L., and Li, S. (2010) Hydrolytic and enzymatic degradation of poly(trimethylene carbonate-co-D,L-lactide) random copolymers with shape memory behavior. Eur. Polym. J., 46 (4), 783-791. 

Structural concepts for tissue-compatible and biodegradable polymers, thermoplastic elastomers, and thermosets with shape memory capabilities will be introduced. Their thermal and mechanical properties and degradation behaviour will be explained. An important precondition for the shape memory effect of polymers is elasticity. An elastic polymeric material consists of flexible segments, so-called network chains, which are connected via netpoints or junctions. The permanent shape of such a polymer is determined by the netpoints. The network chains take a coil-like conformation in unloaded condition. If the polymer is stretched, the network chains become extended... 

Degradable polymer networks having shape memory properties... 

Choi, N.Y, S. Kelch and A. Lendlein (2006), Synthesis, shape-memory functionality and hydrolytical degradation studies on polymer networks from poly(rac-lac-tide)b-poly(propylene oxide)-b-poly(rac-lactide) dimethacrylates. Advanced Engineering Materials, 8(5) pp. 439-445. 

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