Influence of the Preparation Method and Photo-Oxidation Treatment on the Thermal and Gas Transport Properties of Dense Films Based on a Poly(ether-block-amide) Copolymer

Dense films based on the hydrophobic Pebax®2533 were prepared by using solution casting in different solvents as well as compression molding and subjected to photo–aging under ultraviolet (UV) irradiation. The influence of the preparation method, including the casting solvents, as well as the UV irradiation time selected to treat the samples, were evaluated in terms of permeation rates of pure gases (CO2, N2, O2, CH4, He, and H2). The transport data were correlated with the microstructure and surface properties by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), as well as water contact angle measurements. The obtained results showed that a controlled photo-oxidation process reduces the hydrophobicity of the Pebax®2533 films, increasing their permeability without compromising their integrity.

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Super-Efficient Synthesis of Mesh-like Superhydrophobic Nano-Aluminum/Iron (III) Oxide Energetic Films

Materials ◽

10.3390/ma12020234 ◽

2019 ◽

Vol 12 (2) ◽

pp. 234 ◽

Cited By ~ 1

Author(s):

Xiaogang Guo ◽

Taotao Liang

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

Energetic Materials ◽

Scanning Calorimetry ◽

Water Contact ◽

Angle Measurements ◽

Contact Angle Measurements ◽

Aluminum Iron ◽

Potential Applications ◽

One Step

In this study, a novel superhydrophobic nano-aluminum/iron (III) oxide composite has been prepared by a facile one-step process of electrophoretic deposition, with wide potential applications. The optimal suspension included ethanol, acetyl-acetone, and the additives of fluorotriphenylsilane and perfluorodecyltriethoxysilane. The microstructure, wettability, and exothermic performance were analyzed by field emission scanning electron microcopy (FESEM), X-ray diffraction (XRD), water contact angle measurements, and the differential scanning calorimetry (DSC) technique. The water contact angle and the heat-release of the target composites could reach to ~170° and 2.67 kJ/g, and could still keep stable, after exposure for six months, showing a great stability. These results provided an exquisite synthesis of ideas, for designing other superhydrophobic energetic materials with self-cleaning properties, for real industrial application.

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Preparation and Characterization of Chitosan/Poly(Vinyl Alcohol) Blended Films: Mechanical, Thermal and Surface Investigations

E-Journal of Chemistry ◽

10.1155/2011/969062 ◽

2011 ◽

Vol 8 (1) ◽

pp. 91-96 ◽

Cited By ~ 29

Author(s):

Esam A. El-Hefian ◽

Mohamed Mahmoud Nasef ◽

Abdul Hamid Yahaya

Keyword(s):

Contact Angle ◽

Poly Vinyl Alcohol ◽

Scanning Calorimetry ◽

Water Contact ◽

Elongation At Break ◽

Angle Measurements ◽

Static Water Contact Angle ◽

Contact Angle Measurements ◽

Static Water

In this study, blends of chitosan (CS) and polyvinyl alcohol (PVA) (CS/PVA) having various proportions were prepared and characterized by universal mechanical tester, the differential scanning calorimetry (DSC) and contact angle measurements. Studying the mechanical properties of the films showed that blending improved the tensile strength, which increased with increasing PVA content up to 40% while the elongation% at break of the blends was decreased compared to that of the pure components. The obtained results of DSC suggested that some interaction between chitosan and PVA mostly took place. Static water contact angle measurements showed an improvement in the wettability of the obtained films.

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Nanostructured Polymer Brushes With Reversibly Changing Properties

MRS Proceedings ◽

10.1557/proc-727-r2.5 ◽

2002 ◽

Vol 727 ◽

Author(s):

Denys Usov ◽

Manfred Stamm ◽

Sergiy Minko ◽

Christian Froeck ◽

Andreas Scholl ◽

...

Keyword(s):

Polymer Brushes ◽

Phase Segregation ◽

Water Contact ◽

Angle Measurements ◽

Nanostructured Polymer ◽

Contact Angle Measurements ◽

Vertical Segregation ◽

Oxygen Plasma Etching ◽

Grafting From ◽

Photoemission Electron

AbstractWe investigated the interplay between different mechanisms of the lateral and vertical segregation in the synthesized via “grafting from” approach symmetric A/B (where A and B are poly(styrene-co-2,3,4,5,6-pentafluorostyrene) and poly(methylmethacrylate), respectively) polymer brushes upon exposure to different solvents. We used X-ray photoemission electron spectroscopy and microscopy (X-PEEM), AFM, water contact angle measurements, and oxygen plasma etching to study morphology of the brushes. The ripple morphology after toluene (nonselective solvent) revealed elongated lamellar-like domains of A and B polymers alternating across the surface. The dimple-A morphology consisting of round clusters of the polymer A was observed after acetone (selective solvent for B). The top layer was enriched with the polymer B showing that the brush underwent both the lateral and vertical phase segregation. A qualitative agreement with predictions of SCF theory was found.

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Wrinkling Poly(trimethylene 2,5-Furanoate) Free-standing Films: Nanostructure Formation and Physical Properties

10.26434/chemrxiv.11867205.v1 ◽

2020 ◽

Author(s):

Michelina Soccio ◽

Nadia Lotti ◽

Andrea Munari ◽

Esther Rebollar ◽

Daniel E Martínez-Tong

Keyword(s):

Irradiation Time ◽

Polymer Surface ◽

Laser Source ◽

Free Standing ◽

Force Microscopy ◽

Nanostructure Formation ◽

Physicochemical Changes ◽

Angle Measurements ◽

Atomic Force ◽

Contact Angle Measurements

<p>Nanostructured wrinkles were developed on fully bio-based poly(trimethylene furanoate) (PTF) films by using the technique of Laser Induced Periodic Surface Structures (LIPSS). We investigated the effect of irradiation time on wrinkle formation using an UV pulsed laser source, at a fluence of 8 mJ/cm2. It was found that the pulse range between 600 and 4800 pulses allowed formation of periodic nanometric ripples. The nanostructured surface was studied using a combined macro- and nanoscale approach. We evaluated possible physicochemical changes taking place on the polymer surface after irradiation by infrared spectroscopy, contact angle measurements and atomic force microscopy. The macroscopic physicochemical properties of PTF showed almost no changes after nanostructure formation, differently from the results previously found for the terephthalic counterparts, as poly(ethyleneterephthalate), PET, and poly(trimethyleneterephthalate), PTT. The surface mechanical properties of the nanostructured PTF were found to be improved, as evidenced by nanomechanical force spectroscopy measurements. In particular, an increased Young’s modulus and higher stiffness for the nanostructured sample were measured. <br></p>

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On the Effectiveness of Oxygen Plasma and Alkali Surface Treatments to Modify the Properties of Polylactic Acid Scaffolds

Polymers ◽

10.3390/polym13101643 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1643

Author(s):

Ricardo Donate ◽

María Elena Alemán-Domínguez ◽

Mario Monzón

Keyword(s):

Surface Properties ◽

Enzymatic Degradation ◽

Oxygen Plasma ◽

Physicochemical Characterization ◽

Surface Treatments ◽

Carboxyl Groups ◽

Scanning Calorimetry ◽

Water Contact ◽

Angle Measurements ◽

3D Printed

Surface modification of 3D-printed PLA structures is a major issue in terms of increasing the biofunctionality and expanding the tissue engineering applications of these parts. In this paper, different exposure times were used for low-pressure oxygen plasma applied to PLA 3D-printed scaffolds. Alkali surface treatments were also evaluated, aiming to compare the modifications introduced on the surface properties by each strategy. Surface-treated samples were characterized through the quantification of carboxyl groups, energy-dispersive X-ray spectroscopy, water contact angle measurements, and differential scanning calorimetry analysis. The change in the surface properties was studied over a two-week period. In addition, an enzymatic degradation analysis was carried out to evaluate the effect of the surface treatments on the degradation profile of the 3D structures. The physicochemical characterization results suggest different mechanism pathways for each type of treatment. Alkali-treated scaffolds showed a higher concentration of carboxyl groups on their surface, which enhanced the enzymatic degradation rate, but were also proven to be more aggressive towards 3D-printed structures. In contrast, the application of the plasma treatments led to an increased hydrophilicity of the PLA surface without affecting the bulk properties. However, the changes on the properties were less steady over time.

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Epoxy/alumina composite coating on welded steel 316L with excellent wear and anticorrosion properties

Scientific Reports ◽

10.1038/s41598-021-91741-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Maryama Hammi ◽

Younes Ziat ◽

Zakaryaa Zarhri ◽

Charaf Laghlimi ◽

Abdelaziz Moutcine

Keyword(s):

Electrochemical Behaviour ◽

Sem Analysis ◽

Water Contact ◽

Welded Steel ◽

Melted Zone ◽

Angle Measurements ◽

Contact Angle Measurements ◽

Alumina Composite ◽

The Cost ◽

Good Contrast

AbstractThe main purpose of this study is to elaborate anticorrosive coatings for the welded steel 316L, since this later is widely used in industrial field. Hence, within this work we have studied the electrochemical behaviour of different zones of the welded steel 316 in 1 M HCl media. The macrography study of the welded steel has revealed the different areas with a good contrast. We have stated three different zones, namely; melted zone (MZ), heat affected zone (HAZ) and base metal zone (BM). Impedance studies on welded steel 316L were conducted in 1 M HCl solution, coating of Epoxy/Alumina composite was applied on different zones, in order to reveal the anti-corrosion efficiency in each zone. Scanning electron microscopy (SEM) analysis was undertaken in order to check how far the used coating in such aggressive media protects the studied zones and these findings were assessed by water contact angle measurements. The choice of this coating is based on the cost and the safety. We concluded that the Epoxy/Alumina composite has a good protecting effect regarding welded steel in aggressive media.

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PLA-Based Hybrid and Composite Electrospun Fibrous Scaffolds as Potential Materials for Tissue Engineering

Journal of Nanomaterials ◽

10.1155/2017/9246802 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11 ◽

Cited By ~ 9

Author(s):

Anna Magiera ◽

Jarosław Markowski ◽

Elzbieta Menaszek ◽

Jan Pilch ◽

Stanislaw Blazewicz

Keyword(s):

Tissue Engineering ◽

Mechanical Tests ◽

Hybrid Structures ◽

Poly Lactic Acid ◽

Electrospinning Technique ◽

Water Contact ◽

Human Osteoblasts ◽

Angle Measurements ◽

Contact Angle Measurements ◽

Normal Human

The aim of the study was to manufacture poly(lactic acid)- (PLA-) based nanofibrous nonwovens that were modified using two types of modifiers, namely, gelatin- (GEL-) based nanofibres and carbon nanotubes (CNT). Hybrid nonwovens consisting of PLA and GEL nanofibres (PLA/GEL), as well as CNT-modified PLA nanofibres with GEL nanofibres (PLA + CNT/GEL), in the form of mats, were manufactured using concurrent-electrospinning technique (co-ES). The ability of such hybrid structures as potential scaffolds for tissue engineering was studied. Both types of hybrid samples and one-component PLA and CNTs-modified PLA mats were investigated using scanning electron microscopy (SEM), water contact angle measurements, and biological and mechanical tests. The morphology, microstructure, and selected properties of the materials were analyzed. Biocompatibility and bioactivity in contact with normal human osteoblasts (NHOst) were studied. The coelectrospun PLA and GEL nanofibres retained their structures in hybrid samples. Both types of hybrid nonwovens were not cytotoxic and showed better osteoinductivity in comparison to scaffolds made from pure PLA. These samples also showed significantly reduced hydrophobicity compared to one-component PLA nonwovens. The CNT-contained PLA nanofibres improved mechanical properties of hybrid samples and such a 3D system appears to be interesting for potential application as a tissue engineering scaffold.

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Synthesis, Hydrophilicity and Micellization of Coil–Brush Polystyrene-b-(polyglycidol-g-polyglycidol) Copolymer—Comparison with Linear Polystyrene-b-Polyglycidol

Polymers ◽

10.3390/polym14020253 ◽

2022 ◽

Vol 14 (2) ◽

pp. 253

Author(s):

Mariusz Gadzinowski ◽

Maciej Kasprów ◽

Teresa Basinska ◽

Stanislaw Slomkowski ◽

Łukasz Otulakowski ◽

...

Keyword(s):

Contact Angle ◽

Self Assembly ◽

Original Method ◽

Critical Micellization Concentration ◽

Water Contact ◽

1H And 13C Nmr ◽

Similar Composition ◽

Angle Measurements ◽

Contact Angle Measurements ◽

Static Conditions

In this paper, an original method of synthesis of coil–brush amphiphilic polystyrene-b-(polyglycidol-g-polyglycidol) (PS-b-(PGL-g-PGL)) block copolymers was developed. The hypothesis that their hydrophilicity and micellization can be controlled by polyglycidol blocks architecture was verified. The research enabled comparison of behavior in water of PS-b-PGL copolymers and block–brush copolymers PS-b-(PGL-g-PGL) with similar composition. The coil–brush copolymers were composed of PS-b-PGL linear core with average DPn of polystyrene 29 and 13 of polyglycidol blocks. The DPn of polyglycidol side blocks of coil–b–brush copolymers were 2, 7, and 11, respectively. The copolymers were characterized by 1H and 13C NMR, GPC, and FTIR methods. The hydrophilicity of films from the linear and coil–brush copolymers was determined by water contact angle measurements in static conditions. The behavior of coil–brush copolymers in water and their critical micellization concentration (CMC) were determined by UV-VIS using 1,6-diphenylhexa-1,3,5-trien (DPH) as marker and by DLS. The CMC values for brush copolymers were much higher than for linear species with similar PGL content. The results of the copolymer film wettability and the copolymer self-assembly studies were related to fraction of hydrophilic polyglycidol. The CMC for both types of polymers increased exponentially with increasing content of polyglycidol.

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Improved de-inking of inkjet-printed paper using environmentally friendly atmospheric pressure low temperature plasma for paper recycling

Scientific Reports ◽

10.1038/s41598-019-50495-4 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Rodolphe Mauchauffé ◽

Seung Jun Lee ◽

Isaac Han ◽

Sang Hyeong Kim ◽

Se Youn Moon

Keyword(s):

Plasma Treatment ◽

Atmospheric Pressure ◽

Paper Recycling ◽

Temperature Plasma ◽

Water Contact ◽

Angle Measurements ◽

Natural Energy ◽

Contact Angle Measurements ◽

Speed Up ◽

Uv Visible

Abstract Nowadays, due to environmental pollution and natural energy consumption caused by waste paper, many researches are being conducted on the reuse of printed-paper. To recycle the paper, de-inking has to be performed. In this article, in order to reduce the use of the commonly used de-inking chemicals, the effect of an atmospheric pressure helium plasma treatment on the de-inking enhancement of printed-paper is studied. Through colorimeter and UV-visible spectrometer measurements the plasma treatment is shown to speed up the de-inking. While SEM observations and FTIR measurements suggest that the paper quality is retained upon plasma treatment, the increase of surface hydrophilicity measured by water contact angle measurements, compared to non-treated paper, is believed to enhance the fiber swelling of the paper and lead to a faster ink removal.

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Non-woven Membranes Electrospun from Polylactic Acid Incorporating Silver Nanoparticles as Biocide

MRS Proceedings ◽

10.1557/opl.2012.285 ◽

2012 ◽

Vol 1376 ◽

Cited By ~ 5

Author(s):

Haydee Vargas-Villagran ◽

Elvia Teran-Salgado ◽

Maraolina Dominguez-Diaz ◽

Osvaldo Flores ◽

Bernardo Campillo ◽

...

Keyword(s):

Contact Angle ◽

Silver Nanoparticles ◽

Polylactic Acid ◽

Chloroform Solution ◽

Average Diameter ◽

Electrospinning Process ◽

Water Contact ◽

X Ray Scattering ◽

Angle Measurements ◽

Contact Angle Measurements

ABSTRACTIn this research, we describe the electrospinning processing of polylactic acid (PLA) and the influence of silver nanoparticles on the morphology and microstructure of produced non woven membranes thus produced. The PLA was electrospun from a chloroform solution and a filamentary and granular morphology was obtained, the filaments having an average diameter of 1.25 μm, When silver nanoparticles (of ca. 12 nm size) were incorporated, the filaments diameter was reduced to an average of 0.65 μm, and the density of beads was also reduced. The membranes were rather amorphous, as revealed by X-ray scattering, presumably due to the quenching process associated with the electrospinning process. Water contact angle measurements showed that silver nanoparticles induced significant hidrophobicity in the membranes as neat PLA membrane had a contact angle of 54° and PLA/Ag membrane exhibited an angle of 115°.

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