posted on 2021-07-22, 19:44authored byLinxiuzi Yu, Niboqia Zhang, Ning-Ning Zhang, Qianqian Gu, Yao Xue, Yu-Xi Wang, Cheng-Long Han, Kun Liu, Zhao-Yan Sun, Hu-Jun Qian, Zhong-Yuan Lu
The formation of polymer-patch nanoparticles
(PNPs) involves a
condensation process of grafted chains on a nanoparticle (NP) surface,
which is conventionally achieved via a fine-tuning of the solvent
quality. However, such a critical solvent condition differs dramatically
between polymers, and the formation mechanism of different patchy
structures remains under debate. In this study, we demonstrate by
a combined simulation and experimental study that such a surface-patterning
process can be easily achieved via a simple solvent evaporation process,
which creates a natural nonsolvent condition and is, in principle,
adaptable for all polymers. More importantly, we find that patchy
structures are controlled by a delicate balance between enthalpic
interaction and the entropy penalty of grafted chains. A small variation
of cohesive energy density can lead to a dramatic change in patch
structure. This work offers a robust yet easy approach for the fabrication
of PNPs and provides new insights into polymer segregation on spherical
surfaces.