Local Wear of Catechol-Containing Diblock Copolymer Layers: Wear Volume, Stick-Slip, and Nanomechanical Changes
Local Wear of Catechol-Containing Diblock Copolymer Layers: Wear Volume, Stick-Slip, and Nanomechanical Changes
复制标题
含儿茶酚二嵌段共聚物层的局部磨损：磨损体积、粘滑运动和纳米力学变化
DOI：
10.1021/acs.jpcc.1c06859
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发表时间：
2021-09-21
影响因子：
3.7
通讯作者：
Claesson, Per Martin
中科院分区：
文献类型：
--
作者：
Dobryden, Illia;Steponaviciute, Medeina;Claesson, Per Martin
含有邻苯二酚基团的聚合物已经获得了很大的兴趣，因为它们模仿贻贝粘附蛋白的一个基本特征，允许在水下与各种各样的表面强结合。这一特征使得这类聚合物对于表面改性目的是有意义的，因为层功能可以通过简单的吸附过程引入，其中邻苯二酚基团应该提供对表面的强锚定。在这项工作中，我们利用基于AFM的方法来评估这种聚合物层在水中的耐磨性，并将其与静电驱动吸附提供的耐磨性进行比较。我们特别注意两个嵌段共聚物体系，其中锚定基团在一种情况下是不带电的含儿茶酚的嵌段，在另一种情况下是带正电的含儿茶酚的嵌段。耐磨性的磨损体积方面进行评估，在这里，我们比较与数据的类似共聚物的邻苯二酚组的统计分布。纳米力学性能的监测提供了一种替代的方式来说明磨损的影响，我们使用建模表明，刚度，作为探测的AFM针尖，软层驻留在硬基板上的层的厚度减小而增加。粘滑特性也进行了评价。
Polymers containing catechol groups have gained a large interest, as they mimic an essential feature of mussel adhesive proteins that allow strong binding to a large variety of surfaces under water. This feature has made this class of polymers interesting for surface modification purposes, as layer functionalities can be introduced by a simple adsorption process, where the catechol groups should provide a strong anchoring to the surface. In this work, we utilize an AFM-based method to evaluate the wear resistance of such polymer layers in water and compare it with that offered by electrostatically driven adsorption. We pay particular attention to two block copolymer systems where the anchoring group in one case is an uncharged catechol-containing block and in the other case a positively charged and catechol-containing block. The wear resistance is evaluated in terms of wear volume, and here, we compare with data for similar copolymers with statistical distribution of the catechol groups. Monitoring of nanomechanical properties provides an alternative way of illustrating the effect of wear, and we use modeling to show that the stiffness, as probed by an AFM tip, of the soft layer residing on a hard substrate increases as the thickness of the layer decreases. The stick-slip characteristics are also evaluated.