Femtosecond Laser Produced Hydrophobic Hierarchical Structures on Additive Manufacturing Parts

With the recent expansion of additive manufacturing (AM) in industries, there is an intense need to improve the surface quality of AM parts. A functional surface with extreme wettability would explore the application of AM in medical implants and microfluid. In this research, we propose to superimpose the femtosecond (fs) laser induced period surface structures (LIPSS) in the nanoscale onto AM part surfaces with the micro structures that are fabricated in the AM process. A hierarchical structure that has a similar morphology to a lotus leaf surface is obtained by combining the advantages of liquid assisting fs laser processing and AM. A water contact angle (WCA) of 150° is suggested so that a super hydrophobic surface is achieved. The scanning electron microscopy (SEM) images and X-ray photoelectron spectroscopy (XPS) analysis indicate that both hierarchical structures and higher carbon content in the laser processed area are responsible for the super hydrophobicity.

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One-Step Preparation of Durable Super-Hydrophobic MSR/SiO2 Coatings by Suspension Air Spraying

Micromachines ◽

10.3390/mi9120677 ◽

2018 ◽

Vol 9 (12) ◽

pp. 677 ◽

Cited By ~ 4

Author(s):

Zhengyong Huang ◽

Wenjie Xu ◽

Yu Wang ◽

Haohuan Wang ◽

Ruiqi Zhang ◽

...

Keyword(s):

Contact Angle ◽

Adhesion Strength ◽

Contact Angle Hysteresis ◽

Surface Hardness ◽

Hierarchical Structures ◽

Hydrophobic Surface ◽

Water Contact ◽

Hydrophobic Coating ◽

Mechanical Durability ◽

One Step

In this study, we develop a facial one-step approach to prepare durable super-hydrophobic coatings on glass surfaces. The hydrophobic characteristics, corrosive liquid resistance, and mechanical durability of the super-hydrophobic surface are presented. The as-prepared super-hydrophobic surface exhibits a water contact angle (WCA) of 157.2° and contact angle hysteresis of 2.3°. Mico/nano hierarchical structures and elements of silicon and fluorine is observed on super-hydrophobic surfaces. The adhesion strength and hardness of the surface are determined to be 1st level and 4H, respectively. The coating is, thus, capable of maintaining super-hydrophobic state after sand grinding with a load of 200 g and wear distances of 700 mm. The rough surface retained after severe mechanical abrasion observed by atomic force microscope (AFM) microscopically proves the durable origin of the super-hydrophobic coating. Results demonstrate the feasibility of production of the durable super-hydrophobic coating via enhancing its adhesion strength and surface hardness.

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Facile Preparation of a Superhydrophobic iPP Microporous Membrane with Micron-Submicron Hierarchical Structures for Membrane Distillation

Polymers ◽

10.3390/polym12040962 ◽

2020 ◽

Vol 12 (4) ◽

pp. 962 ◽

Cited By ~ 3

Author(s):

Cuicui Hu ◽

Zhensheng Yang ◽

Qichao Sun ◽

Zhihua Ni ◽

Guofei Yan ◽

...

Keyword(s):

Large Scale ◽

Hierarchical Structures ◽

High Water ◽

Membrane Distillation ◽

New Method ◽

Water Contact ◽

Lotus Effect ◽

Thermally Induced ◽

Vacuum Membrane Distillation ◽

Micro Structures

A facile method combining micro-molding with thermally-induced phase separation (TIPS) to prepare superhydrophobic isotacticpolypropylene (iPP) microporous membranes with micron-submicron hierarchical structures is proposed in this paper. In this study, the hydrophobicity of the membrane was controlled by changing the size of micro-structures on the micro-structured mold and the temperature of the cooling bath. The best superhydrophobicity was achieved with a high water contact angle (WCA) of 161° and roll-off angle of 2°, which was similar to the lotus effect. The permeability of the membrane was greatly improved and the mechanical properties were maintained. The membrane prepared by the new method and subjected to 60h vacuum membrane distillation (VMD) was compared with a conventional iPP membrane prepared via the TIPS process. The flux of the former membrane was 31.2 kg/m2·h, and salt rejection was always higher than 99.95%, which was obviously higher than that of the latter membrane. The deposition of surface fouling on the former membrane was less and loose, and that of the latter membrane was greater and steady, which was attributed to the micron-submicron hierarchical structure of the former and the single submicron-structure of the latter. Additionally, the new method is expected to become a feasible and economical method for producing an ideal membrane for membrane distillation (MD) on a large scale.

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An investigation into the anti-icing properties of fabrics used for the outer layer of firefighter clothing

Textile Research Journal ◽

10.1177/0040517518773376 ◽

2018 ◽

Vol 89 (8) ◽

pp. 1500-1511 ◽

Cited By ~ 2

Author(s):

Lun Han ◽

Xiaoming Zhao ◽

Jannette Eveline Kidalla

Keyword(s):

Outer Layer ◽

Photoelectron Spectroscopy ◽

Smooth Surface ◽

Hydrophobic Surface ◽

Hydrophobic Property ◽

Water Contact ◽

Hydrophobic Coating ◽

Before And After ◽

Coating Method ◽

Fabric Surface

The anti-icing properties of fabrics can be considered as involving two parts, the super-hydrophobic property and the ease of ice removal property. In this study, a super-hydrophobic surface was built on to the outer layer of firefighter clothing using nano-silica, C13H13F17O3Si, C19H42O3Si and PU-2540 using a coating method. This coating stops water drops from staying on the fabric surface easily. At the same time, an ultra-smooth surface was built on to the super-hydrophobic surface already created on the fabric using perfluoropolyethers (PFPE) oil by a dipping method, which adds an ice removal function to the fabrics. The anti-icing properties of the samples prepared in the research described in this paper have been investigated using field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), ease of ice removal property tests and static water contact angle analysis. At the same time, the thermal protective performance (TPP) of the samples, before and after super-hydrophobic treatment, was studied by a TPP tester. Results show that the super-hydrophobic coating with an ultra-smooth surface can significantly increase the anti-icing properties of the fabrics used for the outer layer of firefighter clothing. C13H13F17O3Si and C19H42O3Si can improve the hydrophobic properties of the coating. The anti-icing coating in this paper can increase the TPP of the fabrics.

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UV-Curable Hydrophobic Coatings of Functionalized Carbon Microspheres with Good Mechanical Properties and Corrosion Resistance

Coatings ◽

10.3390/coatings8120439 ◽

2018 ◽

Vol 8 (12) ◽

pp. 439 ◽

Cited By ~ 2

Author(s):

Jiajia Wen ◽

Chengchen Feng ◽

Huijie Li ◽

Xinghai Liu ◽

Fuyuan Ding ◽

...

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Thermogravimetric Analysis ◽

Photoelectron Spectroscopy ◽

Carbon Microspheres ◽

Sem Images ◽

Water Contact ◽

Pencil Hardness ◽

Uv Curable ◽

Functional Product

Polyurethane acrylates (PUAs) are a kind of UV curable prepolymer with excellent comprehensive performance. However, PUAs are highly hydrophilic and when applied outdoors, presenting serious problems caused by rain such as discoloring, losing luster and blistering. Thus, it’s important to improve their hydrophobicity and resistance against corrosion. In this paper, carbon microspheres (CMSs) were modified through chemical grafting method. Active double bonds were introduced onto the surface of organic carbon microspheres (OCMSs) and the functional product was referred to as FCMS. The results of Transmission Electron Microscope (TEM), X-ray Photoelectron Spectroscopy (XPS) and Thermogravimetric analysis (TGA) showed that organic chain segments were successfully connected to the surface of OCMSs and the grafting efficiency was as high as 16%. FCMSs were successfully added into UV-curable polyurethane acrylate prepolymer to achieve a hydrophobic coating layer with good mechanical properties, thermal stability and corrosion resistance. When the addition of FCMSs were 1%, thermogravimetric analysis (TGA) results showed that 5% of the initial mass was lost at 297 °C. The water absorption decreased from 52% to 38% and the water contact angle of the PUA composite increased from 72° to 106°. The pencil hardness increased to 4H and obvious crack termination phenomenon was observed in SEM images. Moreover, the corrosion rate was decreased from 0.124 to 0.076 mm/a.

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Construction and surface/interface behavior of bio-functional surface layer by microwave-excited Ar/H2O plasma-induced polyethylene glycol polymerization

International Journal of Modern Physics B ◽

10.1142/s0217979217440933 ◽

2017 ◽

Vol 31 (16-19) ◽

pp. 1744093

Author(s):

Z. Shao ◽

A. Ogino ◽

M. Nagatsu

Keyword(s):

Surface Layer ◽

Functional Groups ◽

Photoelectron Spectroscopy ◽

Optical Emission ◽

Aging Effect ◽

Hydroxyl Groups ◽

Functional Surface ◽

Interface Behavior ◽

Water Contact ◽

Spacer Layer

Ar/H2O microwave-excited surface-wave plasma-induced grafting-polymerization and crosslinking technique was presented to construct a bio-functional surface layer. Optical emission spectroscopy was used to diagnose Ar/H[Formula: see text]O plasma. The surface/interface behavior especially the aging effect of hydroxyl groups over the grafted PEG spacer layer was investigated by measuring water contact angle and X-ray photoelectron spectroscopy. The results demonstrate that the addition of water vapor into Ar plasma can optimize the concentration of hydroxyl functional groups on surface; grafted PEG spacer layer can provide a long-term hydrophilicity of PU films, and alleviate the aging effect of hydroxyl functional groups.

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Study on the Fabrication of Super-Hydrophobic Surface on Inconel Alloy via Nanosecond Laser Ablation

Materials ◽

10.3390/ma12020278 ◽

2019 ◽

Vol 12 (2) ◽

pp. 278 ◽

Cited By ~ 13

Author(s):

Zhen Yang ◽

Yanling Tian ◽

Yuechao Zhao ◽

Chengjuan Yang

Keyword(s):

Surface Chemistry ◽

Photoelectron Spectroscopy ◽

Hierarchical Structures ◽

Hydrophobic Surface ◽

Ambient Air ◽

Nanosecond Laser ◽

Chemical Compositions ◽

Air Exposure ◽

Inconel Alloy ◽

Nanosecond Laser Ablation

Nanosecond laser ablated metallic surfaces showed initial super-hydrophilicity, and then experienced gradual wettability conversion to super-hydrophobicity with the increase of exposing time to ambient air. Due to the presence of hierarchical structures and change of surface chemistry, the laser-induced Inconel alloy surfaces showed a stable apparent contact angle beyond 150° over 30-day air exposure. The wetting states were proposed to elucidate the initial super-hydrophilicity and the final super-hydrophobicity. The basic fundaments behind the wettability conversion was explored by analyzing surface chemistry using X-ray photoelectron spectroscopy (XPS). The results indicated that the origins of super-hydrophobicity were identified as the increase of carbon content and the dominance of C–C(H) functional group. The C–C(H) bond with excellent nonpolarity derived from the chemisorbed airborne hydrocarbons, which resulted in dramatic reduction of surface-free-energy. This study confirmed that the surface chemistry is not the only factor to determine surface super-hydrophobicity. The laser-induced super-hydrophobicity was attributed to the synergistic effect of surface topography and surface chemical compositions. In this work, the corresponding chemical reaction was particularly described to discuss how the airborne hydrocarbons were attached onto the laser ablated surfaces, which reveals the generation mechanism of air-exposed super-hydrophobic surfaces.

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Fabrication of Superhydrophobic Surfaces on Copper Foil with Stearic Acid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.921 ◽

2011 ◽

Vol 295-297 ◽

pp. 921-924 ◽

Cited By ~ 1

Author(s):

Li Bo Wang ◽

Yang Lu ◽

Xin Xin Cao

Keyword(s):

Stearic Acid ◽

Photoelectron Spectroscopy ◽

Pure Copper ◽

Copper Substrate ◽

High Water ◽

Random Pattern ◽

Mixed Solution ◽

Sem Images ◽

Water Contact ◽

Porous Architecture

Superhydrophobic surface was prepared by hydrothermal method on copper substrate via immersing the clean pure copper substrate into the mixed solution of H2O2and C2H5OH, and then the substrate was heated at 100°C for 1.5 h, followed by modifying with stearic acid. The product was characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. The wettability of the products was also investigated. It was found that the as-prepared surface had a high water contact angle of about 153°. SEM images of the film showed that many irregular micro-nano sheets distributed on the surface in a random pattern. The special porous architecture, with the low surface energy leads to the surface superhydrophobicity.

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Characterization of Flax, Jute, and Sisal Fibers after Sodium Perborate Modification

AATCC Journal of Research ◽

10.14504/ajr.6.6.4 ◽

2019 ◽

Vol 6 (6) ◽

pp. 25-31

Author(s):

Yasemin Seki ◽

Ahmet Çağrı Kılınç ◽

Ramazan Dalmış ◽

Serhan Köktaş ◽

Erdal Çelik

Keyword(s):

Photoelectron Spectroscopy ◽

Crystallinity Index ◽

Hydrophobic Surface ◽

Surface Characteristics ◽

Surface Cleaning ◽

Sodium Perborate ◽

Sem Images ◽

X Ray ◽

Fiber Separation ◽

Sisal Fibers

The aim of this research is to investigate sodium perborate tetrahydrate (SP) modification of cellulosic fibers. Flax, jute, and sisal fibers were treated with aqueous solutions of SP at three different concentrations. The changes in surface characteristics were analyzed using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). No significant changes in the crystallinity index for all fibers tested were observed as SP treatments only produced surface modification. SEM images showed partial removal of non-cellulosic components occurred. Increased SP concentrations led to greater surface cleaning and fiber separation, imparting a more hydrophobic surface character.

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The Study on the Anti-corrosion Performance of NiTi Alloy in Human Body Solution with the Fabricating Processes of Laser Irradiation and PDMS Modification

Journal of Bionic Engineering ◽

10.1007/s42235-021-0011-5 ◽

2021 ◽

Vol 18 (1) ◽

pp. 77-91

Author(s):

Chengjuan Yang ◽

Weiran Cao ◽

Zhen Yang ◽

Meng Wang ◽

Xiubing Jing ◽

...

Keyword(s):

Laser Irradiation ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Niti Alloy ◽

Hydrophobic Surface ◽

Niti Shape Memory Alloy ◽

Corrosion Performance ◽

Hydrophobic Surfaces ◽

Sliding Angle ◽

Water Contact

AbstractThis paper presents a new and safe method of fabricating super-hydrophobic surface on NiTi Shape Memory Alloy (SMA), which aims to further improve the corrosion resistance performance and biocompatibility of NiTi SMA. The super-hydrophobic surfaces with Water Contact Angle (WCA) of 155.4° ± 0.9° and Water Sliding Angle (WSA) of 4.4° ± 1.1° were obtained by the hybrid of laser irradiation and polydimethylsiloxane (PDMS) modification. The forming mechanism was systematically revealed via Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS). The anti-corrosion of samples was investigated in Simulated Body Fluid (SBF) via the potentiodynamic polarization (PDP) and Electrochemical Impedance Spectroscopy (EIS) tests. PDMS super-hydrophobic coatings showed superior anti-corrosion performance. The Ni ions release experiment was also conducted and the corresponding result demonstrated that the super-hydrophobic samples effectively inhibited the release of Ni ions both in electrolyte and SBF. Besides, biocompatibility was further analyzed, indicating that the prepared super-hydrophobic surfaces present a huge potential advantage in biocompatibility.

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Preparation and properties of polyurethane coatings modified by polysilazane

High Performance Polymers ◽

10.1177/0954008319891758 ◽

2019 ◽

Vol 32 (6) ◽

pp. 611-619 ◽

Cited By ~ 1

Author(s):

Xiaoli Liu ◽

Zhen Ge ◽

Wenguo Zhang ◽

Yunjun Luo

Keyword(s):

Mechanical Property ◽

Photoelectron Spectroscopy ◽

Composite Coatings ◽

Composite Films ◽

Dip Coating ◽

Water Contact ◽

Research Attention ◽

Elongation At Break ◽

Coating Method ◽

Dip Coating Method

Due to their unique physicochemical properties, polysilazanes exhibit excellent performance when combined with some resin matrixes, which had drawn great research attention. In this article, polyurethane (PU) was firstly prepared by polytetrahydrofuran glycol, isophorone diisocyanate, and 1,4-butanediol as main materials. Then, the prepared PU was blended with polysilazane by mixing the two solutions together, which was cured to films via dip-coating method at room temperature. The structure, thermal stability, and surface properties of the composite coatings were investigated by Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and X-ray photoelectron spectroscopy. The results demonstrated that after modification with polysilazane, the heat resistance, hydrophobicity, and mechanical property of the PU coatings were improved. When the content of polysilazane was 6 wt%, the mechanical property of the composite films was optimized, with a maximum tensile strength of 25.7 MPa and elongation at break of 797%. Meanwhile, the water contact angle of the composite film was 107° and the water absorption reached a minimum of 2.1%, which showed improved hydrophobicity and water resistance.

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