Shanghai Key Laboratory of Advanced Polymeric Materials, State Key Laboratory of Bioreactor Engineering, Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
Nanoscale. 2018 Sep 13;10(35):16873-16880. doi: 10.1039/c8nr05310c.
The self-assembly of colloidal nanoparticles is conceptually analogous to the polymerization of reactive monomers in molecular systems. However, less is known about the polymerization of colloidal nanoparticles into supracolloidal polymers. Herein, using coarse-grained molecular dynamics and theoretical analysis, we reveal the self-assembly mechanism and kinetics of colloidal nanoparticles constructed from triblock terpolymers. The results show that the formation pathway of supracolloidal polymers involves monomer condensation and oligomer coalescence through the manner of end-to-end collisions. In contrast to the polymerization kinetics of molecular systems, the simulations and theoretical analysis definitely demonstrate that the growth of supracolloidal polymers obeys diffusion-controlled step-growth polymerization kinetics with a variable rate coefficient, where the growth rate is dependent upon the concentration of colloidal nanoparticles and the molecular information of triblock terpolymers. Our findings possess wide implications for understanding the growth of supracolloidal polymers, which is important for the rational and precise design of one-dimensional self-assembled superstructures with new horizons for biomedical applications.
胶态纳米粒子的自组装在概念上类似于反应性单体在分子体系中的聚合。然而,人们对胶体纳米粒子聚合形成超胶体聚合物的了解较少。本文采用粗粒化分子动力学和理论分析,揭示了由三嵌段共聚物构建的胶体纳米粒子的自组装机制和动力学。结果表明,超胶体聚合物的形成途径包括单体缩合和低聚物聚结,通过端到端碰撞的方式进行。与分子体系的聚合动力学相反,模拟和理论分析明确表明,超胶体聚合物的生长遵循扩散控制的逐步聚合动力学,具有可变的速率系数,其中生长速率取决于胶体纳米粒子的浓度和三嵌段共聚物的分子信息。我们的发现对于理解超胶体聚合物的生长具有广泛的意义,这对于理解具有新生物医学应用前景的一维自组装超结构的合理和精确设计具有重要意义。