Qin Liguo, Hafezi Mahshid, Yang Hao, Dong Guangneng, Zhang Yali
Key Laboratory of Education Ministry for Modern Design & Rotary-Bearing System, Xi'an Jiaotong University, Xianning West Road, Xi'an 710049, China.
Institute of Design Science and Basic Component, Xi'an Jiaotong University, Xianning West Road, Xi'an 710049, China.
Micromachines (Basel). 2019 Jul 23;10(7):490. doi: 10.3390/mi10070490.
To improve the drag-reducing and antifouling performance of marine equipment, it is indispensable to learn from structures and materials that are found in nature. This is due to their excellent properties, such as intelligence, microminiaturization, hierarchical assembly, and adaptability. Considerable interest has arisen in fabricating surfaces with various types of biomimetic structures, which exhibit promising and synergistic performances similar to living organisms. In this study, a dual bio-inspired shark-skin and lotus-structure (BSLS) surface was developed for fabrication on commercial polyurethane (PU) polymer. Firstly, the shark-skin pattern was transferred on the PU by microcasting. Secondly, hierarchical micro- and nanostructures were introduced by spraying mesoporous silica nanospheres (MSNs). The dual biomimetic substrates were characterized by scanning electron microscopy, water contact angle characterization, antifouling, self-cleaning, and water flow impacting experiments. The results revealed that the BSLS surface exhibited dual biomimetic features. The micro- and nano-lotus-like structures were localized on a replicated shark dermal denticle. A contact angle of 147° was observed on the dual-treated surface and the contact angle hysteresis was decreased by 20% compared with that of the nontreated surface. Fluid drag was determined with shear stress measurements and a drag reduction of 36.7% was found for the biomimetic surface. With continuous impacting of high-speed water for up to 10 h, the biomimetic surface stayed superhydrophobic. Material properties such as inhibition of protein adsorption, mechanical robustness, and self-cleaning performances were evaluated, and the data indicated these behaviors were significantly improved. The mechanisms of drag reduction and self-cleaning are discussed. Our results indicate that this method is a potential strategy for efficient drag reduction and antifouling capabilities.
为提高海洋装备的减阻和防污性能，借鉴自然界中发现的结构和材料是必不可少的。这是因为它们具有诸如智能、微小型化、分级组装和适应性等优异特性。制造具有各种仿生结构的表面引起了人们极大的兴趣，这些表面展现出与生物体相似的、有前景的协同性能。在本研究中，开发了一种双仿生鲨鱼皮和莲花结构（BSLS）表面，用于在商用聚氨酯（PU）聚合物上制造。首先，通过微铸法将鲨鱼皮图案转移到PU上。其次，通过喷涂介孔二氧化硅纳米球（MSNs）引入分级微纳结构。通过扫描电子显微镜、水接触角表征、防污、自清洁和水流冲击实验对双仿生基底进行了表征。结果表明，BSLS表面呈现出双仿生特征。微纳莲花状结构位于复制的鲨鱼皮齿上。在双处理表面观察到接触角为147°，与未处理表面相比，接触角滞后降低了20%。通过剪切应力测量确定了流体阻力，发现仿生表面的减阻率为36.7%。在高速水持续冲击长达10小时的情况下，仿生表面保持超疏水状态。评估了蛋白质吸附抑制、机械稳健性和自清洁性能等材料性能，数据表明这些性能得到了显著改善。讨论了减阻和自清洁的机制。我们的结果表明，该方法是一种具有高效减阻和防污能力的潜在策略。
