Fu Si, Zhang Binbin, Miao Zhiying, Li Zhenyang, Tu Rong, Zhang Song, Li Bao-Wen
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
Nanomaterials (Basel). 2022 Jul 28;12(15):2591. doi: 10.3390/nano12152591.
Chemically exfoliated nanosheets have been extensively employed as functional nanofillers for the fabrication of polymer nanocomposites due to their remarkable electrical, magnetic and optical properties. However, achieving a good dispersion of charged nanosheets in polymer matrix, which will determine the performance of polymer nanocomposites, remains a challenge. Herein, we investigated the dispersion and aggregation behavior of negatively charged CaNbO (CNO) perovskite nanosheets in negatively charged sodium alginate (SA) aqueous dispersion using dynamic light scattering (DLS). When CNO nanosheets meet with SA, aggregation and coagulation inevitably occurred owing to the absorption of SA on nanosheets. By controlling the electrostatic attraction between positively charged poly(ethylene imine) (PEI) and negatively charged SA, the charge density and hydrodynamic size of SA can be tuned to enable the good dispersion of CNO nanosheets in SA. This result may provide a new strategy to achieve the good dispersion of charged nanosheets in charged polymers for the rational design of multifunctional nanocomposites.
由于具有卓越的电学、磁学和光学性能，化学剥离的纳米片已被广泛用作制备聚合物纳米复合材料的功能性纳米填料。然而，要使带电纳米片在聚合物基体中实现良好分散（这将决定聚合物纳米复合材料的性能），仍然是一项挑战。在此，我们使用动态光散射（DLS）研究了带负电的钙铌矿型纳米片（CaNbO，简称CNO）在带负电的海藻酸钠（SA）水分散体中的分散和聚集行为。当CNO纳米片与SA相遇时，由于SA在纳米片上的吸附，不可避免地会发生聚集和凝聚。通过控制带正电的聚乙烯亚胺（PEI）与带负电的SA之间的静电吸引力，可以调节SA的电荷密度和流体动力学尺寸，从而使CNO纳米片在SA中实现良好分散。这一结果可能为在带电聚合物中实现带电纳米片的良好分散提供一种新策略，以合理设计多功能纳米复合材料。
