scholarly journals Preparation, Structure, and Properties of Polystyrene-Microsphere-Reinforced PEG-Based Hydrogels

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2605
Author(s):  
Chen Zhang ◽  
Zhanping Zhang ◽  
Yuhong Qi
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Surface Energy ◽  
In Situ Polymerization ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Confocal Laser ◽  
Polystyrene Microspheres ◽  
Polystyrene Microsphere ◽  
Soap Free Emulsion Polymerization

To improve the mechanical strength and practicability of hydrogels, polystyrene microspheres with core–shell structure were prepared by the soap-free emulsion polymerization, polyethylene glycol hydrogels with polystyrene microspheres by the in-situ polymerization. The structure, morphology, roughness, swelling property, surface energy, and mechanical properties of the microspheres and hydrogels were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, confocal laser microscopy, swelling test, contact angle measurement, and compression test. The results showed that they have certain swelling capacity and excellent mechanical properties, and can change from hydrophobic to hydrophilic surface. The reason is that the hydrophilic chain segment can migrate, enrich, and form a hydration layer on the surface after soaking for a certain time. Introducing proper content of polystyrene microspheres into the hydrogel, the compressive strength and swelling degree improved obviously. Increasing the content of polystyrene microspheres, the surface energy of the hydrogels decreased gradually.

Mechanical Properties of Polyvinyl Chloride Composites Reinforced with Magnesium Borate Whiskers

2013 ◽  
Vol 821-822 ◽  
pp. 1143-1147
Author(s):  
Lie Li ◽  
Xue Ying Nai ◽  
Gui Min Qian ◽  
Dong Hai Zhu ◽  
Wu Li
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Room Temperature ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Magnesium Borate ◽  
Binding Force ◽  
Adsorbed Layers ◽  
Surface Contact Angle ◽  
Scanning Electron

To improve the strength and toughness performance of PVC, the resin reinforced with magnesium borate whiskers (MBOW ) were prepared by mixing whiskers into liquid PVC at room temperature. The effects of borate coupling agent (SBW-III) and contents of MBOw (0~30wt%) on tensile of PVC and composites were studied. The compatibility, hydrophilicity and morphology of MBOw/PVC composites were characterized by Fourier transform infrared spectroscopy ( FTIR), surface contact angle measurement and scanning electron microscopy (SEM) respectively. The results show that both the chemical bonding and physically adsorbed layers exist between MBOw and SBW-III. The surface of modified MBOw is hydrophobic which improves the binding force between PVC and treated MBOw, and the dispersibility of MBOw in PVC significantly. The tensile and the elastic modulus of the SBW-III-treated MBOw /PVC composites increase in comparison to that of the composites filled with untreated MBOw.

Effect of 2D Alpha-Zirconium Phosphate Nanosheets in Interfacial Tension Reduction and Wettability Alteration: Implications for Enhanced Oil Recovery

SPE Journal ◽  
2022 ◽  
pp. 1-13
Author(s):  
Song Qing ◽  
Hong Chen ◽  
Li-juan Han ◽  
Zhongbin Ye ◽  
Yihao Liao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Interfacial Tension ◽  
Oil Recovery ◽  
Zirconium Phosphate ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Wettability Alteration ◽  
Tetrabutylammonium Hydroxide ◽  
Transmission Electron ◽  
2D Nanosheets

Summary α-Zirconium phosphate (α-ZrP) nanocrystals were synthesized by refluxing method and subsequently exfoliated into extremely thin 2D nanosheets by tetrabutylammonium hydroxide (TBAOH) solution. Dynamic light scattering, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to characterize the size distribution and morphology of α-ZrP nanosheets. Interfacial tension (IFT) and contact angle measurement were conducted by different concentrations of α-ZrP nanosheets solutions. The results displayed that the wettability of porous media surface was altered from oleophilic to hydrophilic and the IFT decreased with the increasing of α-ZrP nanosheets concentrations. A new method was proposed to calculate the Hamaker constant for 2D α-ZrP nanosheets. The calculated results displayed that α-ZrP nanosheets were not easy to agglomerate under experimental environment and when the interaction energy barrier increased, the transport amount of α-ZrP nanosheets also increased. Coreflooding tests were also performed with various concentrations and the oil recovery efficiency increased from 33.59 to 51.26% when α-ZrP nanosheets concentrations increased from 50 to 1,000 ppm.

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

2020 ◽  
Vol 20 (3) ◽  
pp. 1780-1789 ◽  
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.

Super-Hydrophobic Surfaces Improve Corrosion Resistance of Fe3Al-Type Intermetallic in Seawater

2008 ◽  
Vol 47-50 ◽  
pp. 173-176 ◽  
Author(s):  
Tao Liu ◽  
Kin Tak Lau ◽  
Shou Gang Chen ◽  
Sha Cheng ◽  
Yan Sheng Yin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Contact Angle ◽  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Hydrophobic Surface ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Atomic Force ◽  
Scanning Electron

A novel super-hydrophobic film was prepared by myristic acid (CH3(CH2)12COOH) chemically adsorbed onto the polyethyleneimine (PEI) coated Fe3Al-type intermetallic wafer. The film character and structure were probed with contact angle measurement, scanning electron microscopy (SEM) and atomic force microscope (AFM). The results suggest that the structure of the film is similar to lotus and the seawater contact angle is larger than 150◦. Moreover, the corrosion resistances of untreated and modified samples in seawater were investigated by electrochemical impedance spectroscopy (EIS). Experimental results show that the corrosion rate of Fe3Al-type intermetallic with super-hydrophobic surface decreases dramatically because of its special microstructure.

scholarly journals Protection of Urban Art Painting: A Laboratory Study

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 162
Author(s):  
Andrea Macchia ◽  
Sara Capriotti ◽  
Laura Rivaroli ◽  
Silvestro Antonio Ruffolo ◽  
Mauro Francesco La Russa
Keyword(s):  
Electron Microscopy ◽  
Contact Angle ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Urban Spaces ◽  
Colorimetric Analysis ◽  
Urban Art ◽  
The Public ◽  
Outdoor Environments ◽  
Water Repellence

Urban art is a form of artistic visual expression and communication that is created in the street and generally in the public dimension of urban spaces. Often these kinds of artworks are in outdoor environments, and they usually suffer from atmospheric weathering and anthropic vandalism. Recently, several strategies have been used to limit or remove the effects of such vandalism. Currently, the use of quartz paints is growing among artists; such paints after setting are more porous and rough on the surface with respect to regular paints. The aim of the study is to assess the performance of anti-graffiti coatings on quartz artworks paints. Two anti-graffiti products were chosen, and their behaviors were assessed in the laboratory by means of contact angle measurement, water capillary test, colorimetric analysis, and optical and electron microscopy. Results showed good water repellence efficacy of the tested products, demonstrating that they are suitable for the protection of urban art, but at least two applications on the surface are needed to achieve good performance.

EFFECT OF Nd:YAG LASER MELTING ON SURFACE ENERGY OF AZ91D Mg ALLOY

2009 ◽  
Vol 16 (06) ◽  
pp. 801-806 ◽  
Author(s):  
Y. C. GUAN ◽  
W. ZHOU ◽  
H. Y. ZHENG
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Laser Irradiation ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Laser Surface ◽  
Laser Melting ◽  
Acid Base ◽  
Az91d Magnesium Alloy ◽  
Drastic Increase

Laser surface melting is known to alter surface energy and wettability of a few engineering materials, but its effect on magnesium alloys has never been reported. Effort was made to study how Nd : YAG laser irradiation influenced surface energy of an AZ91D magnesium alloy. Contact angle measurement was carried out using three types of liquids to make it possible to calculate the surface energy quantitatively based upon the acid–base theory. The laser irradiation was found to enhance surface wettability significantly and lead to a drastic increase in surface energy from 25.82 to 40.78 mJ/m2. The change in surface property was attributed to the laser-induced refinement of α- Mg and β- Mg 17 Al 12 phases and enrichment of Al in the microstructure.

UV-Durable Superhydrophobic Textiles with UV-Shielding Property by Coating Fibers with ZnO/SiO2 Core/Shell Particles

2012 ◽  
Vol 441 ◽  
pp. 351-355 ◽  
Author(s):  
Chao Hua Xue ◽  
Wei Yin ◽  
Shun Tian Jia ◽  
Jian Zhong Ma
Keyword(s):  
Electron Microscopy ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Core Shell ◽  
Uv Shielding ◽  
Transmission Electron ◽  
Blocking Property ◽  
Poly Ethylene ◽  
Shell Particles ◽  
Surface Morphologies

ZnO/SiO2 core/shell particles were fabricated and coated on poly (ethylene terephthalate) (PET) textiles, followed by hydrophobization with hexadecyltrimethoxysilane, to achieve superdrophobic surfaces with UV-shielding property. Transmission electron microscopy (TEM) was employed to reveal the fabrication of ZnO/SiO2 core/shell particles. Scanning electron microscopy (SEM) was conducted to investigate the surface morphologies of the textile and the coating of the fibers. UV-Vis spectrophotometry and contact angle measurement indicated that the incorporation of ZnO onto fibers imparted UV-blocking property to the textile surface, while the coating of SiO2 shell on ZnO made the superhydrophobicity of the as-treated PET textile surface UV-durable.

Structural, thermal and mechanical properties of polymer nanocomposites based on organosoluble polyimide with naphthyl pendent group and layered double hydroxide

2016 ◽  
Vol 29 (8) ◽  
pp. 951-959 ◽  
Author(s):  
Mohammad Dinari ◽  
Ahmad Reza Rajabi
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Layered Double Hydroxide ◽  
In Situ Polymerization ◽  
Zinc Nitrate ◽  
Precipitation Reaction ◽  
Nitrate Hexahydrate ◽  
Pendent Group ◽  
Co Precipitation ◽  
Double Hydroxide

In this study, a soluble aromatic polyimide (PI) with naphthyl pendent group was initially synthesized by the reaction of pyromellitic dianhydride (PMDA) with 5-methyl- N,N-bis(4-nitrophenyl)naphthalen-1-amine. Then, via co-precipitation reaction of zinc nitrate hexahydrate and chromium nitrate nonahydrate, Zn/Cr-layered double hydroxide (LDH) was synthesized using hydrothermal techniques. Finally, different novel nanocomposites (NCs) based on PI and Zn/Cr-LDH (1, 2, 4 wt%) were produced through in situ polymerization. The resulting materials were characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, thermogravimetry analysis (TGA), field emission scanning electron microscopy, transmission electron microscopy, and mechanical testing. According to the TGA results, the prepared NCs showed high thermal stability at higher temperature due to the good dispersion and homogeneity of Zn/Cr-LDH in polymeric matrix. Consequently, the mechanical properties of the synthesized NCs were enhanced by the incorporation of 2 wt% Zn/Cr-LDH in the polymer matrix.

Nanomechanical Properties and Surface Wettability of Carbon Films Prepared by Magnetron Sputtering

2014 ◽  
Vol 609-610 ◽  
pp. 357-361
Author(s):  
Wei Wei An ◽  
Xiao Li Zhao ◽  
Le Gu ◽  
Run Zhou Su
Keyword(s):  
Mechanical Properties ◽  
Contact Angle ◽  
Magnetron Sputtering ◽  
Contact Angle Measurement ◽  
Carbon Films ◽  
Angle Measurement ◽  
Surface Wettability ◽  
Nanomechanical Properties ◽  
A Value ◽  
Measurement Results

In this work, carbon films were deposited by magnetron sputtering on silicon substrate. The effect of sputtering time on the surface wettability and mechanical properties of carbon films was investigated. Contact angle measurement was used to analyse surface wettability, and the nanomechanical properties were characterized by nanoindentation. In experiments, the sputtering time was 45 min, 60 min, 75 min and 90 min. The measurement results show that the maximum film hardness was achieved for sputtering time 90 min, with a value of 2.34 GPa. Longer sputtering time resulted in preferable mechanical properties. It was analyzed that the size of the crystal grains on the substrate surface and thickness of the films were increased with the increment of sputtering time. The surface roughness decreased with the increase of sputtering time. Moreover, Youngs modulus increased with sputtering time and the maximum value was 16.94 GPa. The contact angle measurement results show that the prepared films take on the hydrophilicity. The minimum contact angle was achieved for sputtering time 45 min with a value of 54o.

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