Composite Materials and Structures Center, Department of Chemical Engineering and Materials Science, Michigan State University (MSU), East Lansing, Michigan 48824, USA.
ACS Appl Mater Interfaces. 2012 Oct 24;4(10):5079-85. doi: 10.1021/am301438g. Epub 2012 Sep 19.
The difficulty of dispersing cellulose nanofibers (CNFs) in hydrophobic polymers such as poly(lactic acid) (PLA) remains a major obstacle to the expansion of cellulose nanocomposite applications. In this work, we employed the solvent evaporation technique commonly used for drug microencapsulation to suspend PLA in water as microparticles. The suspension of the microparticles was easily mixed with the CNFs prepared by high-pressure homogenization. Water removal by membrane filtration produced CNF sheets filled with the particles. Compression molding of the stacked sheets resulted in nanocomposites with good CNF dispersions. Increases in the modulus and strength (up to 58% and 210%, respectively) demonstrated the load-bearing capability of the CNF network in the composites.
将纤维素纳米纤维 (CNFs) 分散在疏水性聚合物(如聚乳酸)(PLA)中仍然是纤维素纳米复合材料应用扩展的主要障碍。在这项工作中,我们采用常用于药物微胶囊化的溶剂蒸发技术,将 PLA 作为微球悬浮在水中。微球的悬浮液很容易与通过高压匀浆制备的 CNF 混合。通过膜过滤去除水分,生成了填充有颗粒的 CNF 片材。堆叠片材的压缩成型导致具有良好 CNF 分散性的纳米复合材料。模量和强度的增加(分别高达 58%和 210%)证明了复合材料中 CNF 网络的承载能力。