Colloidal characteristics of gelatin-treated clay: Intercalation, stability, wettability, and rheological properties

In this paper, sodium montmorillonite was modified with gelatin of different concentrations, and various colloidal characteristics of the gelatin-treated clays were measured and analyzed in detail. First, the influence of gelatin on the interlayer space of Mt layers was investigated by X-ray diffraction analysis. Moreover, the aggregation of Mt particles was examined using a combination of electron microscopy and particle size distribution experiments, while the variation of the electrical property of Mt was measured using ζ potential test. Gelatin of different concentrations can increase the particle size of Mt in different degrees. The addition of 4% gelatin could improve the ζ potential of Mt from −30.65 to −15.55 mV. The wettability change of modified Mt induced by the adsorption of gelatin was followed by measurements of water contact angle and observations of the morphology of Mt/gelatin membrane through SEM images. 4% gelatin could improve the water contact angle of Mt to 81.3°. Finally, the rheological properties of Mt/gelatin dispersion including shear viscosity and shear stress were measured using a stress-controlled rheometer. All of the results were consistent by showing that the overall colloidal characteristics and behavior of the gelatin-treated Mt strongly varied depending on the gelatin concentration used in the modification process. These results can provide a deep and comprehensive understanding of the colloidal properties of clay/gelatin systems and give important guidance for the performance design and improvement of Mt/gelatin composite materials. Furthermore, this study can also be expanded the application of gelatin and its composites to other fields.

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Preparation of Hydrophobic Nylon Fabric

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501601100106 ◽

2016 ◽

Vol 11 (1) ◽

pp. 155892501601100

Author(s):

Jinmei Du ◽

Lulu Zhang ◽

Jing Dong ◽

Ying Li ◽

Changhai Xu ◽

...

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Surface Energy ◽

Water Contact Angle ◽

Sem Images ◽

Water Contact ◽

Carboxyl Content ◽

Factors Affecting ◽

Nylon Fabric ◽

Butanetetracarboxylic Acid

Surface roughness and surface energy are two important factors affecting the hydrophobicity of nylon fabric. In this study, nylon fabric was treated for hydrophobicity with tetrabutyltitanate (TBT) and octadecylamine (OA) which were respectively responsible for increasing surface roughness and reducing surface energy. In order to enhance the hydrophobicity, In order to further enhance hydrophobicity by increasing available reactive sites, 1,2,3,4–butanetetracarboxylic acid (BTCA) was applied as a pretreatment to the nylon fabric It was found that the carboxyl content of nylon was increased by the BTCA pretreatment. SEM images showed that the TBT treatment produced small particles on nylon fabric which made surface rough. The water contact angle of nylon fabric treated with BTCA, TBT and OA was measured to be 134°, which was much greater than the water contact angle of nylon fabric treated only with OA. This indicated that the surface roughness resulting from the TBT treatment played an important role in improving hydrophobicity of the treated nylon fabric. The resistance to water penetration and the repellency of water spray of nylon fabric treated with BTCA, TBT and OA were respectively measured to be 27.64 mbar and 85 out of 100.

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Synthesis of water-based cationic polyacrylate copolymer emulsion by RAFT polymerization and its application as an inkjet printing agent

Pigment & Resin Technology ◽

10.1108/prt-04-2020-0029 ◽

2020 ◽

Vol 49 (5) ◽

pp. 401-408

Author(s):

Haojia Su ◽

Zhengchun Cai ◽

Zhengwei lv ◽

Yongkang Chen ◽

Yongxin Ji

Keyword(s):

Contact Angle ◽

Particle Size ◽

Epoxy Resin ◽

Water Contact Angle ◽

Inkjet Printing ◽

Raft Polymerization ◽

Printing Industry ◽

Water Contact ◽

Content Type ◽

Ethyl Methacrylate

Purpose In this work, the authors used reversible addition-fragmentation transfer (RAFT) polymerization to develop a new cationic acrylate modified epoxy resin emulsion for water-borne inkjet which have the advantages of both polyacrylate and epoxy resin. The emulsion was successfully used in the canvas coating for inkjet printing. This paper aims to contribute to the development of novel cationic emulsions for inkjet printing industry. Design/methodology/approach In this work, the epoxy acrylate was synthesized from RAFT agent and epoxy resin firstly. Cationic macromolecular emulsifier was prepared by RAFT polymerization, using 2,2’-Azobisisobutyronitrile as initiator, 2-(dimethylamino)ethyl methacrylate and styrene as monomer, which was directly used to prepare the emulsion. The influences of the amount of 2-(dimethylamino)ethyl methacrylate on particle size, zeta potential and water contact angle were studied. Finally, the cationic emulsion was used to print images by inkjet printing. Findings The emulsion has the smallest particle size, the highest potential and the highest water contact angle when the DM content is 13 Wt.%. The transmission electron microscopy analysis reveals the latex particles is core-shell sphere with the diameters in the range 120–200 nm. The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry. Originality/value The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry.

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PES-Ag3PO4/g-C3N4 Mixed Matrix Film Photocatalyst for Degradation of Methyl Orange Dye

Polymers ◽

10.3390/polym13111746 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1746

Author(s):

Hayati Mohamad Mukhair ◽

Abdul Halim Abdullah ◽

Zulkarnain Zainal ◽

Hong Ngee Lim

Keyword(s):

Contact Angle ◽

Methyl Orange ◽

Water Contact Angle ◽

Laser Scanning ◽

Laser Scanning Microscopy ◽

Photoelectron Spectra ◽

X Ray Diffraction ◽

Water Contact ◽

X Ray ◽

Methyl Orange Dye

In the present study, we explored the effectiveness of PES-Ag3PO4/g-C3N4 film photocatalyst in degrading methyl orange dye under visible light irradiation. The PES-Ag3PO4/g-C3N4 film photocatalyst was prepared via a non-solvent-induced phase inversion process and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser scanning microscopy (LSM), X-ray photoelectron spectra (XPS), UV-diffuse reflectance (DRS), and water contact angle. The incorporation of the Ag3PO4/g-C3N4 composite into the PES matrix improved the pristine PES film’s hydrophilicity, as evidenced by the reduction of water contact angle from 79.03° to 54.33° for a film containing 15 wt % of Ag3PO4/g-C3N4 composite. The film’s photoactivity showed that 13 wt % was the best loading of Ag3PO4/g-C3N4 composite, and the degradation performance was maintained up to three cycles. The •O2− and h+ were the predominant species responsible for the methyl orange degradation.

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Highly thermally resistant hydrophobic poly(vinyl alcohol)-silica hybrid nanofibers

Journal of the Serbian Chemical Society ◽

10.2298/jsc171121032h ◽

2018 ◽

Vol 83 (7-8) ◽

pp. 885-897

Author(s):

Ugur Hulusi ◽

Burcu Oktay ◽

Atilla Gungor ◽

Nilhan Kayaman-Apohan

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

Vinyl Alcohol ◽

Sol Gel ◽

Poly Vinyl Alcohol ◽

Water Mixture ◽

Sem Images ◽

Water Contact ◽

Hybrid Nanofibers ◽

Silica Precursor

In this paper, the preparation of hydrophobic and crosslinked poly- (vinyl alcohol)/silica organic?inorganic hybrid nanofibers via the sol?gel electrospinning method is reported. Silica was produced through the acetic acid catalyzed reaction of a silica precursor consisting of dimethyldimethoxysilane (DMDMOS), methyltrimethoxysilane (MTMS), tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane (FAS1313; Dynasylan? F 8261) and phenyltrimethoxysilane (PTMS; Dynasylan? 9165) in a 2-propanol?water mixture. Hybrid nanofibers were obtained by electrospinning the silica precursor and an aqueous PVA solution. Chemical, structural, thermal and surface analyses were conducted by Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy/energy-dispersive X-ray (SEM/EDX) and water contact angle (WCA) methods, respectively. The obtained hybrid nanofibers were insoluble in aqueous solution. SEM images displayed that highly crosslinked and porous structures were obtained and the average fiber diameters of poly(vinyl alcohol) (PVA)/silica nanocomposites were around 70 nm. A nanofiber surface with a water contact angle of 130? was achieved.

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The Study on the Synthesis of Polyfluoroacrylate

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.395-396.351 ◽

2013 ◽

Vol 395-396 ◽

pp. 351-354

Author(s):

Qin Huan Yang

Keyword(s):

Contact Angle ◽

Particle Size ◽

Polymer Film ◽

Water Contact Angle ◽

Film Surface ◽

Contact Angles ◽

Fluoride Content ◽

Water Contact ◽

Copolymer Films ◽

High Fluoride

Cationic polyfluoroacrylate has been synthesized in the dual presence of cationic and non-ionic emulsifiers. Optimization studies indicated that the optimal proportions of cationic emulsifier 1631 and non-ionic emulsifiers FSA and AEO-9 were 1.75%, 1.25%, and 0.08%, respectively. Under these conditions, the conversion to the polymer was 92.5%, the particle size was 142 nm, and the water contact angle on a polymer film surface was 94.0°. With increasing dosage of hydrocarbon emulsifier, the water contact angles of copolymer films decreased dramatically. The magnitude of this decrease for a polymer with low fluoride content was greater than that for a polymer with high fluoride content. The fluorinated emulsifier FSA behaved similarly to the hydrocarbon emulsifier.

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Halloysite Nanotubes Coated by Chitosan for the Controlled Release of Khellin

Polymers ◽

10.3390/polym12081766 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1766 ◽

Cited By ~ 3

Author(s):

Lorenzo Lisuzzo ◽

Giuseppe Cavallaro ◽

Stefana Milioto ◽

Giuseppe Lazzara

Keyword(s):

Contact Angle ◽

Controlled Release ◽

Water Contact Angle ◽

Electrostatic Interactions ◽

Release Kinetics ◽

Halloysite Nanotubes ◽

Hybrid Nanostructures ◽

Water Contact ◽

Ζ Potential ◽

Novel Strategy

In this work, we have developed a novel strategy to prepare hybrid nanostructures with controlled release properties towards khellin by exploiting the electrostatic interactions between chitosan and halloysite nanotubes (HNT). Firstly, khellin was loaded into the HNT lumen by the vacuum-assisted procedure. The drug confinement within the halloysite cavity has been proved by water contact angle experiments on the HNT/khellin tablets. Therefore, the loaded nanotubes were coated with chitosan as a consequence of the attractions between the cationic biopolymer and the halloysite outer surface, which is negatively charged in a wide pH range. The effect of the ionic strength of the aqueous medium on the coating efficiency of the clay nanotubes was investigated. The surface charge properties of HNT/khellin and chitosan/HNT/khellin nanomaterials were determined by ζ potential experiments, while their morphology was explored through Scanning Electron Microscopy (SEM). Water contact angle experiments were conducted to explore the influence of the chitosan coating on the hydrophilic/hydrophobic character of halloysite external surface. Thermogravimetry (TG) experiments were conducted to study the thermal behavior of the composite nanomaterials. The amounts of loaded khellin and coated chitosan in the hybrid nanostructures were estimated by a quantitative analysis of the TG curves. The release kinetics of khellin were studied in aqueous solvents at different pH conditions (acidic, neutral and basic) and the obtained data were analyzed by the Korsmeyer–Peppas model. The release properties were interpreted on the basis of the TG and ζ potential results. In conclusion, this study demonstrates that halloysite nanotubes wrapped by chitosan layers can be effective as drug delivery systems.

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Morphology and Wettability of Nanoporous Aluminium Oxide Film Prepared by Anodization

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.737.174 ◽

2017 ◽

Vol 737 ◽

pp. 174-178

Author(s):

Apichon Watcharenwong ◽

Narudon Saijaioup ◽

Yotsapon Bailuang ◽

Puangrat Kajitvichyanukul

Keyword(s):

Contact Angle ◽

Oxide Film ◽

Water Contact Angle ◽

Aluminium Oxide ◽

Oxide Surface ◽

High Porosity ◽

Sem Images ◽

Water Contact ◽

High Purity Aluminium ◽

Aluminium Oxide Film

Anodic aluminium oxide (AAO) is a well-known material for nanofabrication. To obtain highly ordered nanoporous array, there is anodization process. AAO were fabricated by anodization method utilizing high purity aluminium foil as the substrate. The substrate was degreased with ultrasonic cleaner for 15 minutes. Then the substrate was anodized in an electrolyte of 0.3 M oxalic acid with various potentials: 10, 20, 30, and 40 V and various durations: 10, 30, 60, 120, and 180 minutes at room temperature. Field emission scanning electron microscope (FE-SEM) was used to investigate surface morphology of nanoporous aluminium oxide film. The wettability of nanoporous aluminium oxide surface was estimated by measuring water contact angle (WCA) of water droplets on the nanoporous aluminium oxide surface. The FE-SEM images showed that the pore size was in the range of 12 - 81 nm. This result can indicated that nanopore size of AAO film increased with the increasing of anodization potentials and anodization time. The water contact angle of AAO samples were approximately 90.55 - 44.33 degrees. The result of measurement proved that super hydrophilic surface obtained with the increasing of nanopore size and high porosity of AAO.

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Long-Term Stable Metal Organic Framework (MOF) Based Mixed Matrix Membranes for Ultrafiltration

10.26434/chemrxiv.13399367 ◽

2020 ◽

Author(s):

Muayad Al-shaeli ◽

Stefan J. D. Smith ◽

Shanxue Jiang ◽

Huanting Wang ◽

Kaisong Zhang ◽

...

Keyword(s):

Contact Angle ◽

Water Contact Angle ◽

Mixed Matrix Membranes ◽

Recovery Ratio ◽

Mixed Matrix ◽

Water Contact ◽

Membrane Performance ◽

Metal Organic ◽

Matrix Membranes

In this study, novel <a>mixed matrix polyethersulfone (PES) membranes</a> were synthesized by using two different kinds of metal organic frameworks (MOFs), namely UiO-66 and UiO-66-NH2. The composite membranes were characterised by SEM, EDX, FTIR, PXRD, water contact angle, porosity, pore size, etc. Membrane performance was investigated by water permeation flux, flux recovery ratio, fouling resistance and anti-fouling performance. The stability test was also conducted for the prepared mixed matrix membranes. A higher reduction in the water contact angle was observed after adding both MOFs to the PES and sulfonated PES membranes compared to pristine PES membranes. An enhancement in membrane performance was observed by embedding the MOF into PES membrane matrix, which may be attributed to the super-hydrophilic porous structure of UiO-66-NH2 nanoparticles and hydrophilic structure of UiO-66 nanoparticles that could accelerate the exchange rate between solvent and non-solvent during the phase inversion process. By adding the MOFs into PES matrix, the flux recovery ratio was increased greatly (more than 99% for most mixed matrix membranes). The mixed matrix membranes showed higher resistance to protein adsorption compared to pristine PES membranes. After immersing the membranes in water for 3 months, 6 months and 12 months, both MOFs were stable and retained their structure. This study indicates that UiO-66 and UiO-66-NH2 are great candidates for designing long-term stable mixed matrix membranes with higher anti-fouling performance.

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