MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, and The Engineering Research Center of Membrane and Water Treatment Technology, Ministry of Education, Zhejiang University, Hangzhou 310027, PR China.
Langmuir. 2011 Dec 6;27(23):14180-7. doi: 10.1021/la202877k. Epub 2011 Nov 8.
This study aims to explore the fundamental surface characteristics of polydopamine (pDA)-coated hydrophobic polymer films. A poly(vinylidene fluoride) (PVDF) film was surface modified by dip coating in an aqueous solution of dopamine on the basis of its self-polymerization and strong adhesion feature. The self-polymerization and deposition rates of dopamine on film surfaces increased with increasing temperature as evaluated by both spectroscopic ellipsometry and scanning electronic microscopy (SEM). Changes in the surface morphologies of pDA-coated films as well as the size and shape of pDA particles in the solution were also investigated by SEM, atomic force microscopy (AFM), and transmission electron microscopy (TEM). The surface roughness and surface free energy of pDA-modified films were mainly affected by the reaction temperature and showed only a slight dependence on the reaction time and concentration of the dopamine solution. Additionally, three other typical hydrophobic polymer films of polytetrafluoroethylene (PTFE), poly(ethylene terephthalate) (PET), and polyimide (PI) were also modified by the same procedure. The lyophilicity (liquid affinity) and surface free energy of these polymer films were enhanced significantly after being coated with pDA, as were those of PVDF films. It is indicated that the deposition behavior of pDA is not strongly dependent on the nature of the substrates. This information provides us with not only a better understanding of biologically inspired surface chemistry for pDA coatings but also effective strategies for exploiting the properties of dopamine to create novel functional polymer materials.
本研究旨在探索聚多巴胺（pDA）涂层疏聚物膜的基本表面特性。基于其自聚合和强附着力的特点，通过浸涂在多巴胺水溶液中对聚偏二氟乙烯（PVDF）膜进行表面改性。通过光谱椭圆术和扫描电子显微镜（SEM）评估，发现多巴胺在膜表面上的自聚合和沉积速率随温度的升高而增加。还通过 SEM、原子力显微镜（AFM）和透射电子显微镜（TEM）研究了 pDA 涂层膜的表面形貌变化以及溶液中 pDA 颗粒的大小和形状。pDA 改性膜的表面粗糙度和表面自由能主要受反应温度的影响，而对反应时间和多巴胺溶液浓度的依赖性较小。此外，还通过相同的程序对其他三种典型的疏聚物膜聚四氟乙烯（PTFE）、聚对苯二甲酸乙二醇酯（PET）和聚酰亚胺（PI）进行了改性。这些聚合物膜的亲液性（液体亲和力）和表面自由能在涂覆 pDA 后显著提高，PVDF 膜也是如此。这表明 pDA 的沉积行为并不强烈依赖于基底的性质。这些信息不仅为我们提供了对受生物启发的 pDA 涂层表面化学的更好理解，而且为利用多巴胺的特性来创造新型功能聚合物材料提供了有效的策略。
