Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons UMONS, Place du Parc 20, B-7000 Mons, Belgium.
Biomacromolecules. 2011 Jul 11;12(7):2456-65. doi: 10.1021/bm200581h. Epub 2011 Jun 9.
In the present work, cellulose nanowhiskers (CNWs), extracted from ramie fibers, were incorporated in polylactide (PLA)-based composites. Prior to the blending, PLA chains were chemically grafted on the surface of CNW to enhance the compatibilization between CNW and the hydrophobic polyester matrix. Ring-opening polymerization of l-lactide was initiated from the hydroxyl groups available at the CNW surface to yield CNW-g-PLA nanohybrids. PLA-based nanocomposites were prepared by melt blending to ensure a green concept of the study thereby limiting the use of organic solvents. The influence of PLA-grafted cellulose nanoparticles on the mechanical and thermal properties of the ensuing nanocomposites was deeply investigated. The thermal behavior and mechanical properties of the nanocomposites were determined using differential scanning calorimetry (DSC) and dynamical mechanical and thermal analysis (DMTA), respectively. It was clearly evidenced that the chemical grafting of CNW enhances their compatibility with the polymeric matrix and thus improves the final properties of the nanocomposites. Large modification of the crystalline properties such as the crystallization half-time was evidenced according to the nature of the PLA matrix and the content of nanofillers.
在本工作中，从苎麻纤维中提取的纤维素纳米纤维（CNWs）被掺入到聚乳酸（PLA）基复合材料中。在共混之前，通过化学方法将 PLA 链接枝到 CNW 表面，以增强 CNW 和疏聚酯基体之间的相容性。从 CNW 表面的羟基引发 L-丙交酯的开环聚合，得到 CNW-g-PLA 纳米杂化物。通过熔融共混制备 PLA 基纳米复合材料，以确保研究的绿色概念，从而限制有机溶剂的使用。深入研究了 PLA 接枝纤维素纳米颗粒对后续纳米复合材料的机械和热性能的影响。使用差示扫描量热法（DSC）和动态力学和热分析（DMTA）分别测定了纳米复合材料的热行为和力学性能。显然，CNW 的化学接枝增强了它们与聚合物基体的相容性，从而提高了纳米复合材料的最终性能。根据 PLA 基体的性质和纳米填料的含量，明显证明了结晶性能的大修饰，例如结晶半时间。
