A Simple Mechanochromic Mechanophore Based on Aminothiomaleimide
A Simple Mechanochromic Mechanophore Based on Aminothiomaleimide
复制标题
基于氨基硫代马来酰亚胺的简单力致变色力力团
DOI：
10.1021/acsmacrolett.8b00241
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发表时间：
2021
影响因子：
5.8
通讯作者：
Chen Yongming
中科院分区：
文献类型：
--
作者：
Tan Min;Hu Zhitao;Dai Yunkai;Peng Yanling;Zhou Yecheng;Shi Yi;Li Yuanchao;Chen Yongming
我们报告可视化的机械化学辅助降解的表面拴系的聚（丙烯酸）（PAA）刷在基本的水性缓冲液在纳米到微米的长度尺度通过监测局部蚀刻的硅基板的变化。PAA刷通过表面引发的原子转移自由基聚合制备，并在0.1 M乙醇胺缓冲液（pH 9.0）与0.5 M NaCl中孵育。通过扫描电子显微镜和原子力显微镜监测底层衬底的形态变化。规则形状的坑的外观表明基板的蚀刻，并且它们的数量和大小都随着孵育时间的增加而增加。我们比较了PAA，聚（甲基丙烯酸甲酯）（PMMA），和聚（聚（乙二醇）甲基丙烯酸酯）（PPEGMA）刷接枝在硅基板上的蚀刻行为。孵育7天后，PMMA刷的基底保持完整。在PAA刷系统中，我们发现了一些大的坑的形成，其大小随着时间的推移而增长。PPEGMA刷的基底上出现许多凹坑，但与PAA相比，凹坑的尺寸小得多。我们的研究结果表明，在给定的孵育条件下，接枝聚合物的疏水性和稳定性对底层硅基底的形态变化起着重要作用。
We report visualization of mechanochemically assisted degrafting of surface-tethered poly(acrylic acid) (PAA) brushes in a basic aqueous buffer at nanometer to micrometer length scale by monitoring changes in local etching of silicon substrates. PAA brushes were prepared by surface-initiated atom transfer radical polymerization and incubated in 0.1 M ethanolamine buffer (pH 9.0) with 0.5 M NaCl. Morphological changes of the underlying substrates were monitored by scanning electron microscopy and atomic force microscopy. The appearance of regular-shaped pits indicated etching of the substrate, and both their number and size grew with increasing incubation time. We compared the etching behaviors for PAA, poly(methyl methacrylate) (PMMA), and poly(poly(ethylene glycol) methacrylate) (PPEGMA) brushes grafted on silicon substrates. After incubation for 7 days, the substrate of PMMA brush remained intact. In PAA brush systems, we detected the formation of a few large pits whose size grew in time. Many pits showed up on the substrate of PPEGMA brush but with substantially smaller size compared to PAA. Our findings suggest that hydrophobicity and stability of the grafted polymers play an important role in the morphological changes of the underlying silicon substrates under given incubation conditions.