Lee Junsang, Kang Seung-Kyun
Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea.
Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea.
Micromachines (Basel). 2021 Jun 27;12(7):757. doi: 10.3390/mi12070757.
Polymers with the shape memory effect possess tremendous potential for application in diverse fields, including aerospace, textiles, robotics, and biomedicine, because of their mechanical properties (softness and flexibility) and chemical tunability. Biodegradable shape memory polymers (BSMPs) have unique benefits of long-term biocompatibility and formation of zero-waste byproducts as the final degradable products are resorbed or absorbed via metabolism or enzyme digestion processes. In addition to their application toward the prevention of biofilm formation or internal tissue damage caused by permanent implant materials and the subsequent need for secondary surgery, which causes secondary infections and complications, BSMPs have been highlighted for minimally invasive medical applications. The properties of BSMPs, including high tunability, thermomechanical properties, shape memory performance, and degradation rate, can be achieved by controlling the combination and content of the comonomer and crystallinity. In addition, the biodegradable chemistry and kinetics of BSMPs, which can be controlled by combining several biodegradable polymers with different hydrolysis chemistry products, such as anhydrides, esters, and carbonates, strongly affect the hydrolytic activity and erosion property. A wide range of applications including self-expending stents, wound closure, drug release systems, and tissue repair, suggests that the BSMPs can be applied as actuators on the basis of their shape recovery and degradation ability.
具有形状记忆效应的聚合物因其机械性能（柔软性和柔韧性）和化学可调性，在航空航天、纺织、机器人技术和生物医学等多个领域具有巨大的应用潜力。可生物降解的形状记忆聚合物（BSMPs）具有独特的优势，即具有长期生物相容性，并且由于最终的可降解产物通过代谢或酶消化过程被吸收或摄取，从而形成零废物副产物。除了应用于预防由永久性植入材料引起的生物膜形成或内部组织损伤以及随后进行二次手术的需求（二次手术会导致二次感染和并发症）之外，BSMPs还因其在微创医疗应用方面而受到关注。通过控制共聚单体的组合和含量以及结晶度，可以实现BSMPs的性能，包括高可调性、热机械性能、形状记忆性能和降解速率。此外，BSMPs的可生物降解化学和动力学可以通过将几种具有不同水解化学产物（如酸酐、酯和碳酸盐）的可生物降解聚合物组合来控制，这强烈影响水解活性和侵蚀性能。包括自膨胀支架、伤口闭合、药物释放系统和组织修复在内的广泛应用表明，基于其形状恢复和降解能力，BSMPs可以用作致动器。
