Characterization and Mechanism of a New Superhydrophobic Deicing Coating Used for Road Pavement

Owing to its high efficiency and low environmental impact, superhydrophobic deicing coating material has a bright future for application on road pavements. In this paper, a heterogeneous nucleation ice crystal growth model is proposed, with particular focus on the effect of surface roughness and the contact angle. The ice suppression mechanism of superhydrophobic materials is determined by this model and experimentally verified. The experimental results of the water contact angle and anti-skid tests illustrated that the prepared TiO2–octadecanoic acid coating material has a contact angle greater than 150° and good skid resistance. The freezing test confirms that the applied coating on the surface can effectively delay the crystallization of water droplets and maintain the waterdrop’s semi-spherical shape after freezing. The microstructure observation demonstrates the TiO2–octadecanoic acid material has a good micro-nano mastoid structure. Consequently, the proposed coating materials could possibly be utilized for effectively enhancing the deicing performance of pavements.

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Addition of Cellulose Nanofibers to Control Surface Roughness for Hydrophobic Ceramic Coatings

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19430 ◽

2021 ◽

Vol 21 (8) ◽

pp. 4492-4497

Author(s):

Eun Ae Shin ◽

Gye Hyeon Kim ◽

Jeyoung Jung ◽

Sang Bong Lee ◽

Chang Kee Lee

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Surface Energy ◽

Water Contact Angle ◽

Ceramic Coating ◽

Cellulose Nanofibers ◽

Ceramic Coatings ◽

Coating Material ◽

Textured Surface ◽

Water Contact

Hydrophobic ceramic coatings are used for a variety of applications. Generally, hydrophobic coating surfaces are obtained by reducing the surface energy of the coating material or by forming a highly textured surface. Reducing the surface energy of the coating material requires additional costs and processing and changes the surface properties of the ceramic coating. In this study, we introduce a simple method to improve the hydrophobicity of ceramic coatings by implementing a textured surface without chemical modification of the surface. The ceramic coating solution was first prepared by adding cellulose nanofibers (CNFs) and then applied to a polypropylene (PP) substrate. The surface roughness increased as the amount of added CNFs increased, increasing the water contact angle of the surface. When the amount of CNFs added was corresponding to 10% of the solid content, the surface roughness average of the area was 43.8 μm. This is an increase of approximately 140% from 3.1 μm (the value of the surface roughness of the surface without added CNFs). In addition, the water contact angle of the coating with added CNF increased to 145.0°, which was 46% higher than that without the CNFs. The hydrophobicity of ceramic coatings with added CNFs was better because of changes in the surface topography. After coating and drying, the CNFs randomly accumulated inside the ceramic coating layer, forming a textured surface. Thus, hydrophobicity was improved by implementing a rugged ceramic surface without revealing the surface of the CNFs inside the ceramic layer.

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Waterproof-breathable PTFE nano- and Microfiber Membrane as High Efficiency PM2.5 Filter

Polymers ◽

10.3390/polym11040590 ◽

2019 ◽

Vol 11 (4) ◽

pp. 590 ◽

Cited By ~ 12

Author(s):

Xiao Li ◽

Xiao-Xiong Wang ◽

Tian-Tian Yue ◽

Yuan Xu ◽

Ming-Liang Zhao ◽

...

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

High Efficiency ◽

Filtration Efficiency ◽

Poly Vinyl Alcohol ◽

Fiber Membrane ◽

Gas Filtration ◽

Electrospinning Technique ◽

Water Contact ◽

Microfiber Membrane

This study shows the feasibility of using electrospinning technique to prepare polytetrafluoroethylene/poly (vinyl alcohol) (PTFE/PVA) nanofibers on PTFE microfiber membrane as substrate. Then, PVA in the fiber membrane was removed by thermal treatment at about 350 °C. Compared to PTFE microfiber substrates, the composite PTFE fiber membranes (CPFMs) have improved filtration efficiency by 70% and water contact angle by 23°. Experimental test data showed that the water contact angle of the sample increased from about 107° to 130°, the filtration efficiency of PM2.5 increased from 44.778% to 98.905%, and the filtration efficiency of PM7.25 increased from 66.655% to 100% due to the electrospun PTFE nanofiber layer. This work demonstrates the potential of CPFMs as a filter for the production of indoor or outdoor dust removal and industrially relevant gas filtration.

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Research on Thermal Reflection and Cooling Curing Coating Material of Nano Modified Emulsified Asphalt for Urban Road Pavement

E3S Web of Conferences ◽

10.1051/e3sconf/202126102051 ◽

2021 ◽

Vol 261 ◽

pp. 02051

Author(s):

Yongqiang Zhong

Keyword(s):

Substrate Material ◽

Temperature Data ◽

Coating Material ◽

Construction Technology ◽

Coating Materials ◽

Urban Road ◽

Reflective Coating ◽

Road Pavement ◽

Pavement Temperature ◽

Emulsified Asphalt

Based on the development of thermal reflective coating materials at home and abroad, modified emulsified asphalt was selected as the substrate material and nano TiO2 was selected as the filler. Different filler dosage was selected, the optimal ratio of thermal reflective coating was obtained by analyzing the pavement temperature data measured in the field experiment. Finally, the construction technology of pavement thermal reflection coating material is described in detail.

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Simple method of fabrication of hydrophobic coatings for polyurethanes

Open Chemistry ◽

10.2478/s11532-011-0094-7 ◽

2011 ◽

Vol 9 (6) ◽

pp. 1039-1045 ◽

Cited By ~ 12

Author(s):

Beata Butruk ◽

Paulina Ziętek ◽

Tomasz Ciach

Keyword(s):

Contact Angle ◽

High Efficiency ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Acoustic Microscopy ◽

Water Contact ◽

Simple Method ◽

Hydrophobic Coatings ◽

Grafting Reaction

AbstractThe aim of this study was to develop a method of manufacturing versatile hydrophobic coatings for polymers. Authors present a simple technique of polyurethane (PU) surface modification with covalently attached silicones (PDMS) or fluorocarbons (PFC). Diisocyanates were applied as linker molecules. The obtained coatings were characterized using spectroscopic analysis (FTIR), scanning acoustic microscopy (SAM) and water contact angle measurements. FTIR analysis revealed high efficiency of grafting reaction. The results of contact angle measurement indicated significant increase of hydrophobicity — from 66° (unmodified PU) to 113° (PU grafted with PDMS) and 118° (PU grafted with PFC). Acoustic microscopy analysis confirmed satisfactory homogeneity and smoothness of the fabricated layers. In vitro cell tests revealed non-adherent properties of the surfaces. Both, MTT assay and fluorescence staining confirmed non-cytotoxicity of the coatings, which makes them potential candidates for use in biomedical applications.

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An Effect of Viscosity of Coating Materials on Silicon Micro-Patterning Arrays for Superhydrophobic Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.93-94.447 ◽

2010 ◽

Vol 93-94 ◽

pp. 447-450 ◽

Cited By ~ 1

Author(s):

N. Atthi ◽

O. Nimittrakoolchai ◽

Sitthisuntorn Supothina ◽

J. Supadech ◽

W. Jeamsaksiri ◽

...

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

Surface Property ◽

Superhydrophobic Surface ◽

Rough Surfaces ◽

Coating Materials ◽

Water Contact ◽

Viscous Material ◽

Micro Patterning

Two different viscous coating materials, which are Polydimethylsiloxane (PDMS) mixed with 10%wt of Dicumylperoxide (DCP), and Semifluorinate Silane (SFS), were applied to silicon micro-asperity. The cosine’s Young and viscosity of those coating materials are -0.3584,-0.3496 and 3.176x10-3, 1.339 x10-3 Pas, respectively. The rough surfaces with nine asperity shapes were studied. The results shown that, pillar shape has an effect on water contact angle (WCA): Stripe asperity cannot make the average WCA greater than 150. When consider the pillar asperity, the WCA falls between 152 and 157, which exhibits a superhydrophobic surface property. However, actual WCA of the micro-asperity coated with PDMS+10%wt of DCP is lower than that coated with SFS around 1 to 7. High viscous material makes the asperity size bigger than the design and decreases the WCA: the low viscous material is more suitable for coating on the asperities.

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Ultra-robust Superhydrophobic/superoleophilic Stainless Mesh Coated by PTFE/SiO2 for Oil/water Separation

MRS Advances ◽

10.1557/adv.2018.604 ◽

2018 ◽

Vol 4 (07) ◽

pp. 359-367 ◽

Cited By ~ 1

Author(s):

Chaolang Chen ◽

Ding Weng ◽

Awais Mahmood ◽

Jiadao Wang

Keyword(s):

Contact Angle ◽

Self Assembly ◽

High Efficiency ◽

Water Contact ◽

Water Separation ◽

Low Surface Energy ◽

Assembly Method ◽

Potential Applications ◽

Oil Water Separation ◽

Oil Water

AbstractIn this study, a superhydrophobic and superoleophilic stainless mesh coated with polytetrafluoroethylene/silicon dioxide (PTFE/SiO2) was fabricated through electrostatic self-assembly method followed by sintering treatment. The PTFE was utilized to construct low-surface-energy surface and the SiO2 nanoparticles were added to enhance its surface roughness. The as-prepared stainless mesh exhibited desirable superhydrophobicity and superoleophilicity with a water contact angle of 152° and oil contact angle of 0°. The coated stainless mesh could separate a variety of oil/water mixtures with high efficiency and it also exhibited good recyclability. Moreover, the corrosion-resistance of stainless mesh was greatly improved by coating it with PTFE. The thermogravimetric analysis (TGA) measurements showed that the coated mesh could withstand high temperature of up to 430°C, indicating excellent thermal-resistance. It is believed that this ultra-robust stainless mesh would have significant potential applications in industry.

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Preparation of High-Efficiency Flame-Retardant and Superhydrophobic Cotton Fabric by a Multi-Step Dipping

Coatings ◽

10.3390/coatings11101147 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1147

Author(s):

Jingda Huang ◽

Mengmeng Li ◽

Changying Ren ◽

Wentao Huang ◽

Qiang Wu ◽

...

Keyword(s):

Contact Angle ◽

Flame Retardant ◽

Composite Coating ◽

Cotton Fabric ◽

Cellulose Nanocrystals ◽

Abrasion Resistance ◽

High Efficiency ◽

Oxygen Index ◽

Water Contact ◽

Flame Retardant Properties

Cotton fabric, as an important material, is suffering from some defects such as flammability, easy pollution and so on; therefore, it is important to make a flame-retardant and superhydrophobic modification on cotton fabric. In this study, we demonstrated a preparation of high-efficiency flame-retardant and superhydrophobic cotton fabric with double coated construction by a simple multi-step dipping. First, the fabric was immersed in branched poly(ethylenimine) (BPEI) and ammonium polyphosphate (APP) water dispersions successively, and then immersed in polydimethylsiloxane (PDMS)/cellulose nanocrystals (CNC)-SiO2 toluene dispersion to form a BPEI/APP/PDMS/CNC-SiO2 (BAPC) composite coating on the surface of the cotton fabric. Here, the hydrophobic modified CNC-SiO2 rods were used to construct the superhydrophobic layer and the BPEI/APP mixture was used as the flame-retardant layer, as well as SiO2 particles which could further improve the flame-retardant effect. PDMS was mainly used as an adhesive between the BPEI/APP layer and the CNC-SiO2 layer. The resulting cotton fabric shows outstanding flame-retardant properties, in that the value of oxygen index meter (LOI) reaches 69.8, as well as excellent superhydrophobicity, in that the water contact angle (WCA) is up to 156.6°. Meanwhile, there is a good abrasion resistance, the superhydrophobicity is not lost until the 16th abrasion cycles and the flame retardant retains well, even after 100 abrasion cycles in an automatic vertical flammability cabinet under a pressure of 8.8 kPa.

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Long-Term Stable Metal Organic Framework (MOF) Based Mixed Matrix Membranes for Ultrafiltration

10.26434/chemrxiv.13399367 ◽

2020 ◽

Author(s):

Muayad Al-shaeli ◽

Stefan J. D. Smith ◽

Shanxue Jiang ◽

Huanting Wang ◽

Kaisong Zhang ◽

...

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

Mixed Matrix Membranes ◽

Recovery Ratio ◽

Mixed Matrix ◽

Water Contact ◽

Membrane Performance ◽

Metal Organic ◽

Matrix Membranes

In this study, novel <a>mixed matrix polyethersulfone (PES) membranes</a> were synthesized by using two different kinds of metal organic frameworks (MOFs), namely UiO-66 and UiO-66-NH2. The composite membranes were characterised by SEM, EDX, FTIR, PXRD, water contact angle, porosity, pore size, etc. Membrane performance was investigated by water permeation flux, flux recovery ratio, fouling resistance and anti-fouling performance. The stability test was also conducted for the prepared mixed matrix membranes. A higher reduction in the water contact angle was observed after adding both MOFs to the PES and sulfonated PES membranes compared to pristine PES membranes. An enhancement in membrane performance was observed by embedding the MOF into PES membrane matrix, which may be attributed to the super-hydrophilic porous structure of UiO-66-NH2 nanoparticles and hydrophilic structure of UiO-66 nanoparticles that could accelerate the exchange rate between solvent and non-solvent during the phase inversion process. By adding the MOFs into PES matrix, the flux recovery ratio was increased greatly (more than 99% for most mixed matrix membranes). The mixed matrix membranes showed higher resistance to protein adsorption compared to pristine PES membranes. After immersing the membranes in water for 3 months, 6 months and 12 months, both MOFs were stable and retained their structure. This study indicates that UiO-66 and UiO-66-NH2 are great candidates for designing long-term stable mixed matrix membranes with higher anti-fouling performance.

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