Grigora Maria-Eirini, Terzopoulou Zoe, Tsongas Konstantinos, Bikiaris Dimitrios N, Tzetzis Dimitrios
Digital Manufacturing and Materials Characterization Laboratory, School of Science and Technology, International Hellenic University, 57001 Thessaloniki, Greece.
Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Nanomaterials (Basel). 2022 Jul 31;12(15):2641. doi: 10.3390/nano12152641.
This work aims to improve the properties of poly(lactic acid) (PLA) for future biomedical applications by investigating the effect of montmorillonite (MMT) nanoclay on physicochemical and mechanical behavior. PLA nanocomposite filaments were fabricated using different amounts of MMT (1.0, 2.0, and 4.0 wt.%) and 2 wt.% Joncryl chain extenders. The 3D-printed specimens were manufactured using Fused Filament Fabrication (FFF). The composites were characterized by Gel Permeation Chromatography (GPC), Melt Flow Index (MFI), X-ray Diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). The thermal properties were studied by means of Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Moreover, the hydrophilicity of the PLA/MMT nanocomposites was investigated by measuring the water contact angle. The mechanical behavior of the PLA/MMT nanocomposites was examined with nanoindentation, compression tests, and Dynamic Mechanical Analysis (DMA). The presence of Joncryl, as well as the pretreatment of MMT before filament fabrication, improved the MMT distribution in the nanocomposites. Furthermore, MMT enhanced the printability of PLA and improved the hydrophilicity of its surface. In addition, the results of nanoindentation testing coupled with Finite Element Analysis showed that as the MMT weight fraction increased, as well as an increased Young's modulus. According to the results of the mechanical analysis, the best mechanical behavior was achieved for PLA nanocomposite with 4 wt.% MMT.
本研究旨在通过研究蒙脱石（MMT）纳米粘土对聚乳酸（PLA）物理化学和力学性能的影响，改善其在未来生物医学应用中的性能。使用不同含量的MMT（1.0、2.0和4.0 wt.%）和2 wt.%的容克瑞尔扩链剂制备了PLA纳米复合长丝。采用熔融长丝制造（FFF）工艺制造了3D打印试样。通过凝胶渗透色谱（GPC）、熔体流动指数（MFI）、X射线衍射（XRD）和傅里叶变换红外光谱（FTIR）对复合材料进行了表征。通过差示扫描量热法（DSC）和热重分析（TGA）研究了热性能。此外，通过测量水接触角研究了PLA/MMT纳米复合材料的亲水性。通过纳米压痕、压缩试验和动态力学分析（DMA）研究了PLA/MMT纳米复合材料的力学性能。容克瑞尔的存在以及长丝制造前MMT的预处理改善了MMT在纳米复合材料中的分布。此外，MMT提高了PLA的可打印性并改善了其表面亲水性。此外，纳米压痕测试与有限元分析相结合的结果表明，随着MMT重量分数的增加，杨氏模量也增加。根据力学分析结果，含4 wt.% MMT的PLA纳米复合材料具有最佳的力学性能。
