An Easy Route to Wettability Changes of Polyethylene Terephthalate–Silicon Oxide Substrate Films for High Barrier Applications, Surface-Modified with a Self-Assembled Monolayer of Fluoroalkylsilanes

Inorganic–organic multilayer films consisting of polymers coated with thin inorganic oxidic layers (e.g., SiOx) ensure very high barrier performances against gas and vapor permeation, what makes them packaging materials suitable for sophisticated technical applications, including the encapsulation of photovoltaic devices or quantum dots, barrier films for optical displays, and transparent greenhouse screens. In these fields, surface coating or texturing of the multilayer protective films are effective technologies to improve their self-clean ability, thus reducing the required maintenance and ensuring longer durability and better performances. In this work, we used the self-assembled monolayer (SAM) technique to modify the surface and wetting properties of commercial polyethylene terephthalate-silicon oxide substrate (PET-SiOx) films developed for technical applications requiring a combined high barrier and transparency. The selected surface modifier was the 1H,1H,2H,2H-per-fluorodecyltrichlorosilane (FDTS). The reagent mixture composition was optimized for the lowest water and oil wettability, as well as the highest self-cleaning capacity and performance stability. In particular, for the used PET-SiOx film the best FDTS/film surface for both the lowest water and oil wettability was found to be equal to 26.5 mM/dm2, which changes the surface behavior from very hydrophilic (static water contact angle (CAw) = 21.5°) to hydrophobic (CAw = 101°), and gives a significant increment of the static oil contact angle (CAo) from 27° to 60°. Interestingly, the results demonstrated that the SAM reaction occurred also on the uncoated the PET side. After the SAM treatment, a small increase of the water vapor permeability is observed, probably due to a crack or defect onset of the SiOx coating of the SAM modified films. On this point, atomic force measurements demonstrated an increment of the SiOx coating layer roughness after the SAM treatment execution. Finally, the transparency changes of the SAM treated films, measured in the wavelength range 400–800 nm, were always small, so that the results were acceptable for the films’ use in applications where high transparency is required.

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Nanocomposite Film Based on Cellulose Acetate and Lignin-Rich Rice Straw Nanofibers

Materials ◽

10.3390/ma12040595 ◽

2019 ◽

Vol 12 (4) ◽

pp. 595 ◽

Cited By ~ 9

Author(s):

Mohammad Hassan ◽

Linn Berglund ◽

Ragab Abou-Zeid ◽

Enas Hassan ◽

Wafaa Abou-Elseoud ◽

...

Keyword(s):

Contact Angle ◽

Cellulose Acetate ◽

Rice Straw ◽

Water Vapor Permeability ◽

Light Transmittance ◽

Vapor Permeability ◽

Water Contact ◽

Transparent Films ◽

Force Microscopy ◽

Good Transparency

Nanofibers isolated from unbleached neutral sulfite rice straw pulp were used to prepare transparent films without the need to modify the isolated rice straw nanofibers (RSNF). RSNF with loading from 1.25 to 10 wt.% were mixed with cellulose acetate (CA) solution in acetone and films were formed by casting. The films were characterized regarding their transparency and light transmittance, microstructure, mechanical properties, crystallinity, water contact angle, porosity, water vapor permeability, and thermal properties. The results showed good dispersion of RSNF in CA matrix and films with good transparency and homogeneity could be prepared at RSNF loadings of less than 5%. As shown from contact angle and atomic force microscopy (AFM) measurements, the RSNF resulted in increased hydrophilic nature and roughness of the films. No significant improvement in tensile strength and Young’s modulus was recorded as a result of adding RSNF to CA. Addition of the RSNF did not significantly affect the porosity, crystallinity and melting temperature of CA, but slightly increased its glass transition temperature.

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Preparation and Characterization of a Novel Poly(vinylidene fluoride-co-hexafluoropropylene)/Poly(ethersulfone) Blend Membrane Fabricated Using an Innovative Method of Mixing Electrospinning and Phase Inversion

Polymers ◽

10.3390/polym13050790 ◽

2021 ◽

Vol 13 (5) ◽

pp. 790

Author(s):

Norhan Nady ◽

Noha Salem ◽

Sherif. H. Kandil

Keyword(s):

Contact Angle ◽

Water Vapor ◽

Phase Inversion ◽

Vinylidene Fluoride ◽

Water Vapor Permeability ◽

Vapor Permeability ◽

Water Contact ◽

Static Water Contact Angle ◽

Poly Vinylidene Fluoride ◽

Static Water

In this work, a novel polymeric membrane was innovated in terms of composition and preparation techniques. A blend of poly(vinylidene fluoride-co-hexafluoropropylene) (PcH) and poly(ethersulfone) (PES) (18 wt.% total polymer concentration) was prepared using a N-methylpyrrolidone (NMP) and N, N-Dimethylformamide (DMF) solvents mixture, while Lithium chloride (0.05–0.5 wt.%) was used as an additive. The electrospinning and phase inversion techniques were used together to obtain a novel membrane structure. The prepared membranes were characterized using scanning electron microscope imaging, energy dispersive X-Ray, differential scanning calorimeter, thermogravimetric analysis, and Fourier transfer infrared spectroscopy-attenuated total reflectance analyses. Moreover, the static water contact angle, membrane thickness, porosity, surface roughness as well as water vapor permeability were determined. ImageJ software was used to estimate the average fiber diameter. Additionally, the effect of the change of PcH concentration and coagulation bath temperature on the properties of the fabricated membrane was studied. The novel developed membrane has shown a good efficiency in terms of properties and features, as a membrane suitable for membrane distillation (MD); a high porosity (84.4% ± 0.6), hydrophobic surface (136.39° ± 3.1 static water contact angle), and a water vapor permeability of around 4.37 × 10−5 g·m/m2·day·Pa were obtained. The prepared membrane can be compared to the MD membranes commercially available in terms of properties and economic value.

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Synthesis of Silphenylene-Containing Siloxane Resins Exhibiting Strong Hydrophobicity and High Water Vapor Barriers

Coatings ◽

10.3390/coatings9080481 ◽

2019 ◽

Vol 9 (8) ◽

pp. 481

Author(s):

Chen ◽

Yi ◽

Wu ◽

Tan ◽

Xu ◽

...

Keyword(s):

Contact Angle ◽

Water Vapor ◽

Water Contact Angle ◽

Water Vapor Permeability ◽

Barrier Properties ◽

High Water ◽

Vapor Permeability ◽

One Pot ◽

Water Contact ◽

Thermal Stabilities

The novel phenylenedisilane, 1,4-bis(dimethoxyphenylsilyl)benzene (BDMPD), was successfully synthesized via the reaction between trimethoxyphenylsilane (TMPS) and a Grignard reagent originating from 1,4-dibromobenzene. In comparison to common Grignard reactions, this process was a facile one-pot method. 1H NMR spectroscopy, FT-IR measurements, and elemental analysis confirmed the predicted structure of BDMPD. In addition, vinyl-terminated polysiloxanes containing silphenylene units (VPSSP), which were hydrolytically copolymerized from BDMPD, TMPS, and divinyltetramethyldisiloxane, exhibited excellent thermal stabilities (T10%: 502 °C, Rw%: 76.86 beyond 700 °C) and suitable refractive indices (1.542). Furthermore, water contact angle and water vapor permeability tests confirmed that the fully cured siloxane resins containing VPSSP-based silphenylene units exhibited strong hydrophobicity (water contact angle: 119°) and superior water vapor barrier properties, thereby indicating their potential to serve as strong waterproof coatings for moisture-proof applications or as adhesives for use in immersed equipment.

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Copper to Copper Direct Bonding Assisted by Self-Assembled Monolayer

Volume 4: Electronics and Photonics ◽

10.1115/imece2010-38565 ◽

2010 ◽

Author(s):

D. F. Lim ◽

X. F. Ang ◽

J. Wei ◽

C. M. Ng ◽

C. S. Tan

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

Bonding Temperature ◽

Contact Angle Measurement ◽

Copper Surface ◽

Angle Measurement ◽

Self Assembled Monolayer ◽

Water Contact ◽

Water Contact Angle Measurement ◽

Self Assembled

In this article, a self-assembled monolayer (SAM) is applied onto the copper surface in an attempt to lower the required bonding temperature. Alkane-thiol with 6-carbon chain length is used and tested for bonding experiment. The adsorption of SAM is confirmed by the sharp rise of the water contact angle measurement and the reduced in the surface roughness. Next, the desorption of SAM is done at a high temperature anneal (<300°C) in an inert ambient and its properties are characterized by the water contact angle measurement and XPS. It is found that the water contact angle measurement decreases sharply close back to the contact angle of the pure blanket copper surface after annealing of SAM. The XPS results also show the ability of SAM in protecting Copper surface from oxidation. Finally, shear test is performed on Cu-Cu structures bonded at low temperature (250°C) in order to verify the SAM behavior in protecting the copper surface from oxidation and enhancement for bonding. The wafer pairs with and without SAM are intentionally exposed in clean room environment for few days. The bonded pieces are diced and subject to shear stress and results show that with SAM protection, shear strength is improved due to the enhancement in grain growth as a result of cleaner surface.

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Surface Properties of Superhydrophobic Coatings for Stone Protection

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.8.23 ◽

2009 ◽

Vol 8 ◽

pp. 23-33 ◽

Cited By ~ 8

Author(s):

P.N. Manoudis ◽

I. Karapanagiotis ◽

A. Tsakalof ◽

I. Zuburtikudis ◽

B. Kolinkeová ◽

...

Keyword(s):

Contact Angle ◽

Water Vapor Permeability ◽

Sio2 Nanoparticles ◽

Vapor Permeability ◽

Capillary Absorption ◽

Sem Images ◽

Water Contact ◽

Static Contact ◽

Colorimetric Measurements ◽

Glass Surfaces

Superhydrophobic films are produced by a simple and low cost method. Silica (SiO2) nanoparticles are dispersed in solutions of Rhodorsil 224, a commercial poly(alkyl siloxane) which is used for the protection of outdoor cultural heritage objects, and the suspensions are sprayed on glass surfaces. It is shown that the siloxane-nanoparticle composite films prepared from dispersions of high particle concentrations (≥ 0.5% w/v) exhibit superydrophobic properties (high static contact angle and small hysteresis) which can be rationalized by the Cassie-Baxter model, according to quantitative measurements obtained by SEM images. Siloxane-nanoparticle films are then deposited (sprayed) on “Opuka”, a fine-grained argillite which was used for the restoration of the castle of Prague. It is shown that the treated stone surfaces exhibit superydrophobic properties, similar to the treated glass surfaces. The efficacy of the superhydrophobic films to protect Opuka is evaluated by performing water contact angle, water capillary absorption, water vapor permeability and colorimetric measurements. It is shown that the use of nanoparticles in the protective coating has a positive effect on the results of the aforementioned tests, except for the colorimetric measurements.

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Upcycling of Vine Shoots: Production of Fillers for PHBV-Based Biocomposite Applications

Journal of Polymers and the Environment ◽

10.1007/s10924-020-01884-8 ◽

2020 ◽

Cited By ~ 1

Author(s):

Grégoire David ◽

Laurent Heux ◽

Stéphanie Pradeau ◽

Nathalie Gontard ◽

Hélène Angellier-Coussy

Keyword(s):

Water Vapor ◽

Gas Phase ◽

Mechanical Performance ◽

Low Cost ◽

Water Vapor Permeability ◽

Contact Angles ◽

Vapor Permeability ◽

Water Contact ◽

Median Diameter ◽

Cost Of Materials

Abstract This paper aims at investigating the potential of vine shoots (ViSh) upcycling as fillers in novel poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHBV) based biocomposites. ViSh particles of around 50 µm (apparent median diameter) were obtained combining dry grinding processes, and mixed with PHBV using melt extrusion. Thermal stability and elongation at break of biocomposites were reduced with increasing contents of ViSh particles (10, 20 and 30 wt%), while Young’s modulus and water vapor permeability were increased. It was shown that a surface gas-phase esterification allowed to significantly increase the hydrophobicity of ViSh particles (increase of water contact angles from 59° to 114°), leading to a reduction of 27% in the water vapor permeability of the biocomposite filled with 30 wt% of ViSh. The overall mechanical performance was not impacted by gas-phase esterification, demonstrating that the interfacial adhesion between the virgin ViSh particles and the PHBV matrix was already good and that such filler surface treatment was not required in that case. It was concluded that ViSh particles can be interestingly used as low cost fillers in PHBV-based biocomposites to decrease the overall cost of materials.

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Contact Angle Variation on a Copper Surface Treated With Self-Assembled Monolayer (SAM) of N-octadecyl Mercaptan

Journal of Heat Transfer ◽

10.1115/1.4003891 ◽

2011 ◽

Vol 133 (8) ◽

Author(s):

Yulong Ji ◽

Hsiu-hung Chen ◽

Qingsong Yu ◽

Xuehu Ma ◽

H. B. Ma

Keyword(s):

Contact Angle ◽

Copper Surface ◽

Self Assembled Monolayer ◽

Angle Variation ◽

Self Assembled

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Preparation and Properties of Corn Starch/Chitin Composite Films Cross-Linked by Maleic Anhydride

Polymers ◽

10.3390/polym12071606 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1606

Author(s):

Peng Yin ◽

Jinglong Liu ◽

Wen Zhou ◽

Panxin Li

Keyword(s):

Maleic Anhydride ◽

Corn Starch ◽

Composite Films ◽

Water Vapor Permeability ◽

Contact Angles ◽

Vapor Permeability ◽

Water Contact ◽

Elongation At Break ◽

Shrimp Shell ◽

Starch Films

To improve the functional properties of starch-based films, chitin (CH) was prepared from shrimp shell powder and incorporated into corn starch (CS) matrix. Before blending, maleic anhydride (MA) was introduced as a cross-linker. Composite CS/MA-CH films were obtained by casting-evaporation approach. Mechanical property estimation showed that addition of 0–7 wt % MA-CH improved the tensile strength of starch films from 3.89 MPa to 9.32 MPa. Elongation at break of the films decreased with the addition of MA-CH, but the decrease was obviously reduced than previous studies. Morphology analysis revealed that MA-CH homogeneously dispersed in starch matrix and no cracks were found in the CS/MA-CH films. Incorporation of MA-CH decreased the water vapor permeability of starch films. The water uptake of the films was reduced when the dosage of MA-CH was below 5 wt %. Water contact angles of the starch films increased from 22° to 86° with 9 wt % MA-CH incorporation. Besides, the composite films showed better inhibition effect against Escherichia coli and Staphylococcus aureus than pure starch films.

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