1
|
Callau M, Fajolles C, Leroy J, Verneuil E, Guenoun P. A silicone-based slippery polymer coating with humidity–dependent nanoscale topography. J Colloid Interface Sci 2023; 642:724-735. [PMID: 37037078 DOI: 10.1016/j.jcis.2023.03.198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 03/24/2023] [Accepted: 03/29/2023] [Indexed: 04/05/2023]
Abstract
HYPOTHESIS Slippery Omniphobic Covalently Attached Liquids (SOCAL) have been proposed for making omnirepellent thin films of self-assembled dimethylsiloxane polymer brushes grafted from silica surfaces. Smooth and flat at very small scale, these fluid surfaces could exhibit a more complex multiscale structure though showing very weak contact angle hysteresis (less than 5°). EXPERIMENT In this work, coatings were deposited on glass surfaces from an acidic dimethoxydimethylsilane solution under carefully controlled relative humidity. Ellipsometry mapping was used to analyze the surface structuration with nanometric thickness sensitivity. The sliding properties were determined using a drop shape analyzer with a tilting device, and chemical analyses of the coatings were performed using on-surface techniques (XPS, ATR-FTIR spectroscopy). FINDINGS Coated materials possessed an unexpected surface structure with multiscale semispherical-like features, which surprisingly, did not increase the contact angle hysteresis. A careful study of some parameters of the coating process and the related evolution of the surface properties allowed us to propose a new model of the chemical organization of the polymer to support this remarkable liquid-like behavior. These structures are made of end-grafted strongly adsorbed Guiselin brushes with humidity-dependent thickness: the higher the humidity, the thinner and the more slippery the coating.
Collapse
|
2
|
Abu Jarad N, Rachwalski K, Bayat F, Khan S, Shakeri A, MacLachlan R, Villegas M, Brown ED, Soleymani L, Didar TF. An Omniphobic Spray Coating Created from Hierarchical Structures Prevents the Contamination of High-Touch Surfaces with Pathogens. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2205761. [PMID: 36587985 DOI: 10.1002/smll.202205761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Engineered surfaces that repel pathogens are of great interest due to their role in mitigating the spread of infectious diseases. A robust, universal, and scalable omniphobic spray coating with excellent repellency against water, oil, and pathogens is presented. The coating is substrate-independent and relies on hierarchically structured polydimethylsiloxane (PDMS) microparticles, decorated with gold nanoparticles (AuNPs). Wettability studies reveal the relationship between surface texturing of micro- and/or nano-hierarchical structures and the omniphobicity of the coating. Studies of pathogen transfer with bacteria and viruses reveal that an uncoated contaminated glove transfers pathogens to >50 subsequent surfaces, while a coated glove picks up 104 (over 99.99%) less pathogens upon first contact and transfers zero pathogens after the second touch. The developed coating also provides excellent stability under harsh conditions. The remarkable anti-pathogen properties of this surface combined with its ease of implementation, substantiate its use for the prevention of surface-mediated transmission of pathogens.
Collapse
Affiliation(s)
- Noor Abu Jarad
- School of Biomedical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada
| | - Kenneth Rachwalski
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Fereshteh Bayat
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, L8S 4L7, Canada
| | - Shadman Khan
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, L8S 4L7, Canada
| | - Amid Shakeri
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, L8S 4L7, Canada
| | - Roderick MacLachlan
- Department of Engineering Physics, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L7, Canada
| | - Martin Villegas
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, L8S 4L7, Canada
| | - Eric D Brown
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Leyla Soleymani
- School of Biomedical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada
- Department of Engineering Physics, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L7, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, L8S 4K1, Canada
| | - Tohid F Didar
- School of Biomedical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, L8S 4L7, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, L8S 4K1, Canada
| |
Collapse
|
3
|
Zhao X, Park DS, Choi J, Park S, Soper SA, Murphy MC. Flexible-templated imprinting for fluorine-free, omniphobic plastics with re-entrant structures. J Colloid Interface Sci 2021; 585:668-675. [PMID: 33127056 PMCID: PMC8483707 DOI: 10.1016/j.jcis.2020.10.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 10/23/2022]
Abstract
HYPOTHESIS Compared to vertical micro-pillars, re-entrant micro-structures exhibited superior omniphobicity for suspending liquids to Cassie-Baxter state. However, the existing re-entrant structures rely on complex multi-step deposition and etching procedures. The conventional, rigid-templated imprinting would instead damage the re-entrant structures. This leads to the question: is it possible to preserve the re-entrant curvatures by a flexible-templated imprinting? EXPERIMENTS We facilely imprinted the re-entrant structures on a plastic substrate using a flexible nylon-mesh template. The effect of imprinting time (15-35 min), temperature (110-120 °C) and pressure (15-50 Bar) was investigated. To further improve the liquid-repellency and abrasion resistance, the silica nanoparticles (30-650 nm) along with epoxy resin binder (10 mg/mL) were pre-coated. FINDINGS A one-step imprinting is sufficient to fabricate the re-entrant structures by utilizing flexible nylon-mesh template, without damaging the imprinted structures after the demolding process. The pre-coated silica nanoparticles and epoxy resin (1) improved liquid repellency by introducing hierarchical surface structures (e.g. contact angle hysteresis of olive oil reduced > 10°), and (2) acted as a protective layer against mechanical abrasion (omniphobicity maintained after 25 cycles, ~1.6 kPa sand paper abrasion). Additionally, the fluorine-free post-treatment was sufficient for the omniphobicity on the obtained plastic structures.
Collapse
Affiliation(s)
- Xiaoxiao Zhao
- Center for BioModular Multiscale Systems for Precision Medicine, Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Daniel S Park
- Center for BioModular Multiscale Systems for Precision Medicine, Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Junseo Choi
- Center for BioModular Multiscale Systems for Precision Medicine, Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Sungook Park
- Center for BioModular Multiscale Systems for Precision Medicine, Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Steven A Soper
- Departments of Chemistry and Mechanical Engineering, University of Kansas, Lawrence, KS 66045, United States
| | - Michael C Murphy
- Center for BioModular Multiscale Systems for Precision Medicine, Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, United States.
| |
Collapse
|
4
|
Shi S, Lv C, Zheng Q. Drop Impact on Two-Tier Monostable Superrepellent Surfaces. ACS APPLIED MATERIALS & INTERFACES 2019; 11:43698-43707. [PMID: 31644872 DOI: 10.1021/acsami.9b14880] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Superrepellency is a favorable nonwetting scenario featuring a dramatic reduction of the solid/liquid contact area. The robustness of superhydrophobicity plays a central role in self-cleaning and anti-icing. Drop impacts happen ubiquitously in natural environments and often cause a notable extension of the solid/liquid contact area. This is associated with an enhanced affinity between water and the microtextures and therefore leads to irreversible breakdowns in the superhydrophobicity. This problem remains a major challenge and limits the practical applications of superrepellent materials. In order to find a solution, in this paper, a repeated Cassie-Wenzel-Cassie wetting state transition is studied at the microscale when a drop impacts a two-tier superhydrophobic surface. In this case, the surface is completely dry without any liquid residue after the drop rebounds. The present results exhibit a striking contrast to the conventional perspective. The influence of geometrical parameters of the textured surface on the spreading and retracting behaviors of the impact drops is quantified, as well as the time-dependence scaling laws. From a practical point of view, it is demonstrated that the self-cleaning and dropwise condensation may significantly benefit from this repeated wetting transition. Dirt particles or small droplets in deep textures are able to be taken away so that the functionality and the robustness of the superhydrophobicity may be significantly strengthened. The results reported in this study facilitate the design of functional superrepellent materials.
Collapse
Affiliation(s)
- Songlin Shi
- Department of Engineering Mechanics , Tsinghua University , 100084 Beijing , People's Republic of China
- Center for Nano and Micro Mechanics , Tsinghua University , 100084 Beijing , People's Republic of China
| | - Cunjing Lv
- Department of Engineering Mechanics , Tsinghua University , 100084 Beijing , People's Republic of China
- Center for Nano and Micro Mechanics , Tsinghua University , 100084 Beijing , People's Republic of China
| | - Quanshui Zheng
- Department of Engineering Mechanics , Tsinghua University , 100084 Beijing , People's Republic of China
- Center for Nano and Micro Mechanics , Tsinghua University , 100084 Beijing , People's Republic of China
- State Key Laboratory of Tribology , Tsinghua University , 100084 Beijing , People's Republic of China
| |
Collapse
|