基于PDMS的蘑菇状仿生黏附微阵列新型制造方法

Novel Fabrication Method of Mushroom-shaped Bioinspired Adhesive Microstructure Based on PDMS

受到自然界中壁虎和甲虫脚趾表面微纳纤毛结构的启发,本工作基于聚二甲基硅氧烷(PDMS)提出了一种表面具有蘑菇状微阵列的仿生干黏附材料制造方法,通过进给实验装置对传统支柱状仿生干黏附材料进行“蘸取”,实现了表面蘑菇状微阵列的制造。蘑菇状仿生干黏附材料单根纤维的黏附面积为1.12×10^(-3)mm^(2),最大切向黏附强度为2.65 N/cm^(2),法向黏附强度为5.18 N/cm^(2)。与手工制造方式相比,黏附面积提升了33.74%,黏附强度最大分别提升了225%、280%。结合SEM图、光学显微图、黏附材料与黏附接触面的接触状态和黏着功进行黏附性能的理论分析。利用这一方法,蘑菇状仿生干黏附材料的黏着角减小,微阵列的末端直径、表面平整度、有效黏着功、黏附面积和柔顺性显著提升,材料能够更好地适应接触面,且具有较好的重复性,显著提高了材料的切向和法向黏附强度。本工作为蘑菇状仿生干黏附材料的制造提供了一种新思路。

Inspired by the micro-nano ciliary structures on the toes of geckos and beetles in nature, a kind of biomimetic dry adhesive with mushroom-shaped microarray composed of polydimethylsiloxane(PDMS)was “dipped” and fabricated by a feeding experimental device. The contact area of a single fiber of the mushroom-shaped bionic dry adhesive is 1.12×10^(-3)mm^(2), the maximum shear adhesion strength is up to 2.65 N/cm^(2), and the maximum normal adhesion strength is 5.18 N/cm^(2). Compared with manual manufacturing, the adhesion area increased by 33.74%, and the shear and normal adhesion strength increased by 225% and 280% respectively. Considering the SEM images, optical micrograph, adhesive state and adhesion work between adhesive and contact surface, the adhesion performance was conducted by theoretical analysis. By this method, the adhesion angle of the mushroom-shaped biomimetic dry adhesive was reduced, and the diameter, flatness, effective adhesion work, adhesion area, and flexibility of the microarray were significantly improved. The adhesive could better adapt to the contact surface with good repeatability and significantly improve the shear and normal adhesive strength. This work provides a novel idea for manufacturing mushroom-shaped biomimetic dry adhesive.