Studies of the Roughness of Films Based on Organosols of Silver Nanoparticles by Determining Contact Angles

Electrospun poly(ε-caprolactone) (PCL) fibers containing silver nanoparticles were successfully prepared from PCL solutions added silver collide. The silver collide were obtained by N, N-dimethylformamide (DMF) reducing silver nitrate (AgNO3). The effects of PCL concentration and the content of silver nanoparticles on composite fibers morphology were characterized by field-emission scanning electron microscopy (FESEM). The existence of Ag nanoparticles on the electrospun fibers was approved by X-Ray diffraction (XRD). Simultaneously, the contact angles of fiber membranes were measured. The results indicated that uniform fibers were obtained when PCL concentration was 9wt%, the average diameter of fiber was significantly decreased as increasing the amount of silver collide, and Ag nanoparticles were successfully incorporated into the PCL fibers.

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Superhydrophobic conductive wood with oil repellency obtained by coating with silver nanoparticles modified by fluoroalkyl silane

Holzforschung ◽

10.1515/hf-2014-0226 ◽

2016 ◽

Vol 70 (1) ◽

pp. 63-68 ◽

Cited By ~ 20

Author(s):

Likun Gao ◽

Yun Lu ◽

Jian Li ◽

Qingfeng Sun

Keyword(s):

Silver Nanoparticles ◽

Electronic Devices ◽

Contact Angles ◽

Motor Oil ◽

Ag Nps ◽

Water Contact ◽

Electrically Conductive ◽

Maximal Contact ◽

Wood Surfaces ◽

Modification Of The Surface

AbstractA simple and effective method for preparing superhydrophobic conductive wood surface with super oil repellency is presented in this paper. Silver nanoparticles (Ag NPs) were prepared on wood surfaces by the treatment with AgNO3, followed by a reduction treatment with glucose to generate a dual-size surface roughness. Further modification of the surface coated with Ag NPs with a fluoroalkyl silane led to a superhydrophobic surface with water contact angle of 155.2°. This surface is also super repellent toward motor oil with the maximal contact angles around 151.8°. Interestingly, the dense Ag NPs coating on the surface is electrically conductive. The presented multifunctional coating could be a commercialized for various applications, especially for self-cleaning and biomedical electronic devices.

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Synthesis, performance and growth mechanism of silver nanoparticle coated SERS fiber probe

Matériaux & Techniques ◽

10.1051/mattech/2018061 ◽

2019 ◽

Vol 107 (3) ◽

pp. 305

Author(s):

Mengmei Geng ◽

Yuting Long ◽

Tongqing Liu ◽

Zijuan Du ◽

Hong Li ◽

...

Keyword(s):

Silver Nanoparticles ◽

Absorption Spectrum ◽

Reaction Time ◽

Growth Mechanism ◽

Fiber Optic ◽

Fiber Optic Probe ◽

Visible Absorption ◽

Fiber Probe ◽

Surface Enhanced Raman ◽

Optic Probe

Surface-enhanced Raman Scattering (SERS) fiber probe provides abundant interaction area between light and materials, permits detection within limited space and is especially useful for remote or in situ detection. A silver decorated SERS fiber optic probe was prepared by hydrothermal method. This method manages to accomplish the growth of silver nanoparticles and its adherence on fiber optic tip within one step, simplifying the synthetic procedure. The effects of reaction time on phase composition, surface plasmon resonance property and morphology were investigated by X-ray diffraction analysis (XRD), ultraviolet-visible absorption spectrum (UV-VIS absorption spectrum) and scanning electron microscope (SEM). The results showed that when reaction time is prolonged from 4–8 hours at 180 °C, crystals size and size distribution of silver nanoparticles increase. Furthermore, the morphology, crystal size and distribution density of silver nanoparticles evolve along with reaction time. A growth mechanism based on two factors, equilibrium between nucleation and growth, and the existence of PVP, is hypothesized. The SERS fiber probe can detect rhodamin 6G (R6G) at the concentration of 10−6 M. This SERS fiber probe exhibits promising potential in organic dye and pesticide residue detection.

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Assessment of the bactericidal effect of green synthesized silver nanoparticles against a panel of infectious microorganisms

Planta Medica ◽

10.1055/s-0036-1596752 ◽

2016 ◽

Vol 81 (S 01) ◽

pp. S1-S381

Author(s):

E Antunes ◽

M Mmola ◽

M Meyer ◽

DR Beukes

Keyword(s):

Silver Nanoparticles ◽

Bactericidal Effect ◽

Green Synthesized Silver Nanoparticles

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Flexographic ink-coating interactions: effects of latex variations in coating layers

TAPPI Journal ◽

10.32964/tj15.4.253 ◽

2016 ◽

Vol 15 (4) ◽

pp. 253-262 ◽

Cited By ~ 1

Author(s):

ERIK BOHLIN ◽

CAISA JOHANNSON ◽

MAGNUS LESTELIUS

Keyword(s):

Contact Angles ◽

High Ratio ◽

Print Quality ◽

Particle Sizes ◽

Mixed Composition ◽

Coating Surface ◽

Covered Area ◽

Surface Optical ◽

Flexographic Printing ◽

Coating Formulation

The effect of coating structure variations on flexographic print quality was studied using pilot-coated paperboard samples with different latex content and latex particle sizes. Two latexes, with particle sizes of 120 nm and 160 nm, were added at either 12 parts per hundred (pph) or 18 pph to the coating formulation. The samples were printed with full tone areas at print forces of 25 N and 50 N in a laboratory flexographic printing press using a waterbased ink. A high ratio of uncovered areas (UCAs) could be detected for the samples that contained 18 pph latex printed at a print force of 25 N. UCAs decreased with increased print force and with decreased amounts of latex in the coating formulation. The fraction of latex covered area on the coating surface was estimated to be 0.35–0.40 for the 12 pph, and 0.70–0.75 for the 18 pph samples. The ink penetration depth into the coating layer could be linked to the fraction of latex-free areas on the coating surface. Optical cross section microscopy indicated that a higher printing force did not increase the depth of penetrated ink to any greater extent. Higher printing force did increase contact between plate and substrate, leading to an improved distribution of the ink. This, in turn, increased print density and decreased UCAs. On closer inspection, the UCAs could be categorized as being induced by steep topographic changes. When appearing at other locations, they were more likely to be caused by poor wetting of the surface. To understand the wetting behavior of the coating surface, observed contact angles were compared with calculated contact angles on surfaces of mixed composition.

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Influence of Polymer Charge, Temperature, and Surfactants on Surface Sizing of Liner and Greaseproof Paper With Hydrophobically Modified Starch

TAPPI Journal ◽

10.32964/tj8.2.33 ◽

2009 ◽

Vol 8 (2) ◽

pp. 33-38 ◽

Cited By ~ 3

Author(s):

ANNA JONHED ◽

LARS JÄRNSTRÖM

Keyword(s):

Phase Separation ◽

Contact Angles ◽

Low Ph ◽

Hydrophobically Modified ◽

Paper Sizing ◽

Surface Sizing ◽

Separation Temperature ◽

Hydrophobic Nature ◽

Sizing Agents ◽

Charge Temperature

The aim of this study was to investigate the properties of hydrophobically modified (HM) quaterna-ry ammonium starch ethers for paper sizing. These starches possess temperature-responsive properties; that is, gelation or phase separation occurs at a certain temperature upon cooling. This insolubility of the HM starches in water at room temperature improved their performance as sizing agents. The contact angles for water on sized liner were substantially larger than on unsized liner. When the application temperature was well above the critical phase-separation temperature, larger contact angles were obtained for liner independently of pH compared with those at the lower application temperature. Cobb60 values for liner decreased upon surface sizing, with a low pH and high application temperature giving lower water penetration. Contact angles on greaseproof paper decreased upon sur-face sizing as compared to unsized greaseproof paper, independently of pH and temperature. Greaseproof paper showed no great difference between unsized substrates and substrates sized with HM starch at different pH. This is probably due to the already hydrophobic nature of greaseproof paper. However, the Cobb60 values increased at low pH and low application temperature. Surfactants were added to investigate how they affect the sized surface. Addition of surfactant reduces the contact angles, in spite of indications of complex formation.

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