3D打印聚乳酸的改性研究与应用进展

Research Progress in the Modification and Applications of 3D Printed Polylactic Acid

聚乳酸(PLA)是一种生物可降解热塑性聚酯,是极有前景的生物基可降解材料之一。PLA具有优异的力学性能、良好的可塑性及生物相容性,是理想的3D打印材料。3D打印PLA材料在多个领域尤其是医用方面有巨大的潜力。然而,PLA固有的脆性和较差的耐热、耐水解性限制了它的应用范围。近年来,学者对3D打印PLA的改性进行了大量研究。本文归纳了3D打印PLA的研究进展,分别从共混改性、复合改性、立构复合、涂层法和化学改性这几方面讨论了提高材料性能的原理与方法,并对相关性能进行了分析对比。共混法虽然简单易操作,但不利于材料的均匀化,且有时改性效果不够明显。复合改性向PLA中加入碳基添加剂、金属添加剂、植物纤维等填料,改性同时可赋予3D打印PLA更多功能,但易出现界面不相容等问题。此外,还有立构复合、涂层法、化学改性等新方法具有重要的研究价值。在此基础上,结合目前3D打印PLA在实际应用中的发展情况,分析了3D打印PLA仍存在的问题,对3D打印PLA未来的研究方向进行了展望。

Polylactic acid (PLA) is a biodegradable thermoplastic polyester, which is one of the most promising biodegradable materials. PLA is an ideal 3D printing material with excellent mechanical properties, good plasticity, and biocompatibility. 3D printed PLA materials exhibit high potential in various fields, particularly in biomedical and tissue engineering. However, the inherent brittleness, poor heat-resistance, and inferior hydrolysis resistance limit the applications of PLA materials. Recently, scholars have conducted a number of studies to improve properties of 3D printed PLA. This article summarizes the research progress of 3D printing of PLA materials, including blending, composite preparation, stereo-comple- xation , coating and chemical modification. Major principles and protocols of these methods to improve properties of PLA are discussed, with detailed analysis and comparison of relevant properties. Although blending is easy to operate, it is not conducive to the homogenization of PLA materials, sometimes with limited improvement in properties. Carbon based additives, metal additives, plant fibers, and other fillers provide 3D printed PLA multiple functions. However, interfacial incompatibility remains a problem in composite preparation. Furthermore, new methods, such as stereo-complexation, coating, and chemical modification are also valuable methods to be discovered. Considering the development requirements of 3D printed PLA in practical applications, existing problems in current PLA materials are systematically analyzed to serve as an access threshold for quality 3D printed PLA to be considered in real applications.