Fabrication and characterization of superhydrophobic and superlipophilic silica nanofibers mats with excellent heat resistance

A kind of silica nanofibers (SNF) mats with superhydrophobicity and superlipophilicity as well as excellent heat resistance, had been prepared by modifying of 1, 1, 1, 3, 3, 3-hexamethyldisilazane on electrospun SNF mats. The effects of heat treatment time on properties of modified SNF mats were investigated by scanning electron microscopy, nitrogen absorption analysis, X-ray photoelectron spectroscopy, and contact angle measurement. With high specific surface area 240.1 m2/g, the optimal modified SNF mat approached water contact angle (WCA) 153.2? and fuel contact angle (FCA) 0?, furthermore, even after annealing by 450?C in air for 1h , WCA remained at 135.5? and FCA kept at 3.8?, which opened a new way to improve heat resistance of fuel-water filter paper.

Download Full-text

Effect of Plasma-Induced Polymerization on Contact Angle of Paper

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.1619 ◽

2011 ◽

Vol 396-398 ◽

pp. 1619-1623

Author(s):

Zhao Ping Song ◽

Jun Rong Li ◽

Hui Ning Xiao

Keyword(s):

Contact Angle ◽

Photoelectron Spectroscopy ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Polymer Grafting ◽

Hydrophobic Property ◽

Cellulose Fibres ◽

Water Contact ◽

X Ray ◽

Factors Associated

Hydrophobic modification of cellulose fibres was conducted by plasma-induced polymer grafting in an attempt to increase the hydrophobicity of paper. Two hydrophobic monomers, i.e., butyl acrylate (BA) and 2-ethylhexyl acrylate (2-EHA) were grafted on cellulose fibres, induced by atmospheric cold plasma. Various influencing factors associated with the plasma-induced grafting were investigated, including the contact time and reaction temperature with monomers, and the dosage of monomers. Contact-angle measurement, infrared spectrum (IR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used to ascertain the occurrence of the grafting. The results showed that the hydrophobic property of the modified paper sheet was improved significantly after the plasma-induced grafting. The water contact angle on the surface of the paper reached up to higher than125°.

Download Full-text

Fabrication of superhydrophobic cotton fabrics through wrapping silica with plasma-induced grafting polymerization

Textile Research Journal ◽

10.1177/0040517517748492 ◽

2017 ◽

Vol 89 (3) ◽

pp. 401-410 ◽

Cited By ~ 3

Author(s):

Yongqiang Li ◽

Chao Zou ◽

Jianzhong Shao ◽

Ya’nan Li

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

Cotton Fabric ◽

Photoelectron Spectroscopy ◽

Contact Angle Measurement ◽

Cotton Fabrics ◽

Angle Measurement ◽

Water Contact ◽

Washing Durability ◽

Before And After

Cotton fabric is commonly used in daily life, but it is easily wetted and contaminated by liquid. Herein, we present a simple and environmentally friendly plasma technology for hydrophobic modification of cotton fabric. In order to endow superhydrophobicity to cotton fabric, helium plasma inducing graft polymerization of 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane (D4Vi) was utilized to wrap SiO2 particles on cotton fabrics. Cotton fabrics were successively dipped in silica sol and D4Vi, then treated by plasma. Cotton fabrics before and after modification were characterized by using field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and water contact angle measurement. The experimental results showed that the cotton-SiO2-D4Vi consisted of nanoscale SiO2 protrusions and low-surface-energy film polymerized by D4Vi. In addition, the one wrapped SiO2 of 161 nm presented excellent hydrophobicity, washing durability, and repellency toward different types of liquids with a water contact angle of 152°.

Download Full-text

Adsorption of Hyperbranched Polysiloxysilane Modified with Triethoxy Group onto the Silicon Wafer

High Performance Polymers ◽

10.1177/0954008307081213 ◽

2007 ◽

Vol 19 (5-6) ◽

pp. 700-710 ◽

Cited By ~ 3

Author(s):

Yasuko Yamada ◽

Tomoyasu Hirai ◽

Ryohei Kikuchi ◽

Teruaki Hayakawa ◽

Masa-Aki Kakimoto

Keyword(s):

Contact Angle ◽

Silicon Wafer ◽

Photoelectron Spectroscopy ◽

Dynamic Contact Angle ◽

Dynamic Contact ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Wafer Surface ◽

Water Contact ◽

Silicon Wafer Surface

Triethoxysilyl functionalized hyperbranched polsiloxysilanes at the focal (FT-HBPSs) and terminal (TT-HBPSs) positions were synthesized to investigate adsorption behavior onto a silicon wafer surface. The surface of the silicon wafer adsorbed with the HBPSs was characterized by X-ray photoelectron spectroscopy, atomic force microscopy (AFM), static and dynamic water contact angle measurements. The AFM images indicated the formation size of dot-like structures were approximately 200 nm. The presence of vinyl terminal groups of FT-HBPSs permitted conversion of the surface from a non-polar hydrocarbon to a polar hydroxylated or carboxylated structures. After the polarity was changed, the surface properties were also studied using the above surface analysis techniques. The dynamic contact angle measurement indicated that the silicon wafer surface modified by FT-HBPSs was more hydrophilic in water than TT-HBPS. This behavior can be explained by the difference of connecting points between HBPS and the silicon wafer surface.

Download Full-text

Study on modifying the Au surface by thiol compound for biosensor application

Science and Technology Development Journal ◽

10.32508/stdj.v19i4.691 ◽

2016 ◽

Vol 19 (4) ◽

pp. 178-187

Author(s):

Khoa Thanh Nhat Phan ◽

Thanh Trung Nguyen ◽

Tuan Van Phan ◽

Binh Van Pham ◽

Tung Xuan Thanh Pham ◽

...

Keyword(s):

Contact Angle ◽

Horseradish Peroxidase ◽

Laser Beam ◽

Water Contact Angle ◽

Treatment Time ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Water Contact ◽

Biosensor Application ◽

Optimal Values

In cantilever-based biosensor, Au surface plays two essential roles: as a surface to reflect laser beam and as a surface to be modified and thus functionalize the sensor. In this paper, we researched on modifying the Au surface by cysteamine and glutaraldehyde to make it reactive toward amine substances. Cysteamine concentration, cysteamine treatment time and glutaraldehyde treatment time were investigated to find optimal values. The data of chromogenic reaction catalyzed by horseradish peroxidase (HRP) and the data of water contact angle measurement were combined to find the optimal values. The results showed that the modification with 5 mM cysteamine in ethanol for 16 h and glutaraldehyde for 1 h would create the Au surface which can react optimally with amine substances.

Download Full-text

Effects of Surface Treatments of Polycaprolactone Scaffolds on their Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.747.178 ◽

2013 ◽

Vol 747 ◽

pp. 178-181 ◽

Cited By ~ 2

Author(s):

Wasana Kosorn ◽

Boonlom Thavornyutikarn ◽

Wanida Janvikul

Keyword(s):

Contact Angle ◽

Plasma Treatment ◽

Alkaline Hydrolysis ◽

Photoelectron Spectroscopy ◽

Atomic Ratio ◽

Contact Angle Measurement ◽

Contact Angles ◽

Angle Measurement ◽

Water Contact ◽

Oh Groups

Polycaprolactone (PCL) was surface modified with alkaline hydrolysis by NaOH and/or low pressure oxygen (O2) plasma treatment. The hydrolysis was conducted in two different stages: one was performed prior to PCL scaffold fabrication by a high pressure supercritical CO2 technique; the other was carried out after the fabrication. The resulting hydrolyzed PCL scaffolds, with pore sizes in the range of 150-250 μm, were denoted as pre-HPCL and post-HPCL, respectively. Both non-hydrolyzed and hydrolyzed PCL scaffolds were subsequently subjected to the plasma treatment, to further enhance the hydrophilicity of the scaffolds. The surface morphology, wettability and chemical composition of all PCL scaffolds were analyzed by scanning electron microscopy (SEM), water contact angle measurement, and X-ray photoelectron spectroscopy (XPS), respectively. It was found that the surface of the scaffolds turned from fairly smooth to highly rough after the hydrolysis and plasma treatment, particularly when both treatments were in use. The post-hydrolysis induced more surface roughness, compared to the pre-hydrolysis. In addition, the water contact angles on the scaffolds enormously reduced after the treatments; plasma treatment, however, showed a more prominent effect than the alkaline hydrolysis. Although expressing a zero-degree contact angle, the plasma-treated pre-HPCL scaffold was wetted more readily than the plasma-treated post-HPCL. These were in good agreement with the XPS results; interestingly, the plasma-treated pre-HPCL scaffold exhibited the greatest O/C atomic ratio among the PCL scaffolds. This indicated its highest extent of PCL chain oxidation, a degradation of ester groups into-COOH and-OH groups.

Download Full-text

Superhydrophobic functionalized cellulosic paper by copper hydroxide nanorods for oils purification

Scientific Reports ◽

10.1038/s41598-021-95784-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ahmed S. Belal ◽

Jehan El Nady ◽

Azza Shokry ◽

Shaker Ebrahim ◽

Moataz Soliman ◽

...

Keyword(s):

Contact Angle ◽

Filter Paper ◽

Separation Efficiency ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Absorption Capacity ◽

Morphological Properties ◽

Copper Hydroxide ◽

Immersion Method ◽

Water Contact

AbstractOily water contamination has been sighted as one of the most global environmental pollution. Herein, copper hydroxide nanorods layer was constructed onto cellulosic filter paper surface cured with polydopamine, Ag nanoparticles, and Cu NPs through immersion method. This work has been aimed to produce a superhydrophobic and superoleophilic cellulosic filter paper. The structure, crystalline, and morphological properties of these modified cellulosic filter paper were investigated. Scanning electron microscope images confirmed that the modified surface was rougher compared with the pristine surface. The contact angle measurement confirmed the hydrophobic nature of these modified surfaces with a water contact angle of 169.7°. The absorption capacity was 8.2 g/g for diesel oil and the separation efficiency was higher than 99%. It was noted that the flux in the case of low viscosity solvent as n-hexane was 9663.5 Lm−2 h−1, while for the viscous oil as diesel was 1452.7 Lm−2 h−1.

Download Full-text

Preparation of TiO2–SiO2 Hybrid Nanosols Coated Flame-Retardant Polyester Fabric Possessing Dual Contradictory Characteristics of Superhydrophobicity and Self Cleaning Ability

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17166 ◽

2020 ◽

Vol 20 (3) ◽

pp. 1780-1789 ◽

Cited By ~ 5

Author(s):

Priyanka Katiyar ◽

Shraddha Mishra ◽

Anurag Srivastava ◽

N. Eswara Prasad

Keyword(s):

Electron Microscopy ◽

Contact Angle ◽

Flame Retardant ◽

Protective Clothing ◽

Sol Gel ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Water Contact ◽

Vis Spectroscopy ◽

Self Cleaning

TiO2, SiO2 and their hybrid nanocoatings are prepared on inherent flame retardant textile substrates from titanium(IV)iso-proproxide (TTIP) and tetraethoxysilane (TEOS) precursors using a sol–gel process followed by hydrothermal treatment. The coated samples are further functionalized by hexadecyltrimethoxysilane (HDTMS) to impart superhydrophobicity. Sample characterization of the nanosols, nanoparticles and coated samples are investigated using, X-ray diffractometer, transmission electron microscopy, scanning electron microscopy, UV-Vis spectroscopy, contact angle measurement. Stain degradation test under mild UV irradiation shows almost 54% degradation of coffee stain within 4 hours measured by Spectrophotometer. UV-Vis Absorption Spectroscopy demonstrates complete degradation of methyl orange colorant within 3 hours. Hybrid nanosol coated and HDTMS modified inherent flame retardant polyester surfaces show apparent water contact angle as ~145°, which is much closer to proximity of superhydrophobic surfaces. Thus, the novelty of present work is, by using sol–gel technique, a bi-functional textile surface has been developed which qualifies the very specific requirements of protective clothing like self-cleaning property (imparted by TiO2 nanoparticles) and superhydrophobicity (imparted by SiO2 nanoparticles and further surface modification by HDTMS), which are entirely contradictory in nature, in a single fabric itself. Thus developed textile surfaces also possess the other attributes of protective clothing like flame retardancy and air permeability.

Download Full-text

High Loading Capacity and Wear Resistance of Graphene Oxide/Organic Molecule Assembled Multilayer Film

Frontiers in Chemistry ◽

10.3389/fchem.2021.740140 ◽

2021 ◽

Vol 9 ◽

Author(s):

Li Chen ◽

Gang Wu ◽

Yin Huang ◽

Changning Bai ◽

Yuanlie Yu ◽

...

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Multilayer Films ◽

Thickness Measurement ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Film Structure ◽

Silicon Substrates ◽

Water Contact ◽

Macro Scale

Taking advantage of the strong charge interactions between negatively charged graphene oxide (GO) sheets and positively charged poly(diallyldimethylammonium chloride) (PDDA), self-assembled multilayer films of (GO/PDDA)n were created on hydroxylated silicon substrates by alternating electrostatic adsorption of GO and PDDA. The formation and structure of the films were analyzed by means of water contact angle measurement, thickness measurement, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Meanwhile, tribological behaviors in micro- and macro- scale were investigated by AFM and a ball-on-plate tribometer, respectively. The results showed that (GO/PDDA)n multilayer films exhibited excellent friction-reducing and anti-wear abilities in both micro- and macro-scale, which was ascribed to the special structure in (GO/PDDA)n multilayer films, namely, a well-stacked GO–GO layered structure and an elastic 3D crystal stack in whole. Such a film structure is suitable for design molecular lubricants for MEMS and other microdevices.

Download Full-text